Just like I promised, here is an overview about the topics that were discussed so that you won't forget everything
What are dreams / when do we dream?Dreams are most likely about processing experiences.
During the day you've got all sorts of sensory input - if you think you saw something, this assumption will automatically be corrected if contradictory input is given. In the night this contradictory input is missing, therefore you see what you think you saw.
Sleep is divided into several sleep phases, ranging from light to very deep sleep. During light sleep/sleep onset one might experience hypnagogic imagery (strange/random sounds, images etc.). While you are asleep, you are in sleep paralysis and only your eyes move.
The REM (rapid eye movement) phase is the phase where the most dreams happen and is a relatively light sleep phase. REM starts at around 70-90 minutes after falling asleep and the first REM phase lasts for roughly 5-10 minutes and is most likely followed by a short awakening. The longer you've been asleep, the longer these REM periods will last.
How to influence dreams – while being awake & how our mind worksOur mind has schemas or models for nearly everything. For objects ("rectangular surface supported by four small pillars" - our mind has a model for that and it is called "a table"), language, memory, reasoning, stories etc.
For example: you can't tell if someone is lying or not if you don't have the mental models for truth or lies.
To influence your dreams while you are awake, simply keep yourself busy with something. If you focus on something during the day, this will somehow manifest itself in your dreams. Everyone that has played tetris for a few hours straight will most likely continue to play tetris in their dreams - or be confronted with some related problem, like arranging geometrical shapes (eg. tables) in a limited space (eg. storage room) with maximum efficiency.
You can exploit this by working on a story for your dreams and keeping yourself occupied with this story, daydream about it. Sooner or later some elements will appear in your dreams.
My personal experience here is, that it took a few weeks for some small perhaps not even that relevant details to be part of my dreams and after a few months I suddenly found myself in the whole story I wrote. Now I have access to positive elements from these stories in a lot of my dreams.
lucid dreamsLucid dreams are all about knowing that you are currently dreaming (or not dreaming).
The first step you should take is to improve your dream recall so that you are able to recall at least one dream per night.
This is necessary to remember your lucid dreams (even though my personal experience tells me that those dreams are usually not forgotten that easy) and more importantly to recognise patterns that often occur in your dreams. You might find yourself at school often in your dreams or perhaps your car won't work - you might even have a reoccurring nightmare.
To improve your dream recall, try keeping a dream journal. The very moment you wake up, don't immediately start thinking about your daily routine or what you'll have to do today. Instead, think about the last images, sounds or emotions that are most likely still floating around your head - even if they might seem like faint echoes at that time. Spend a few minutes trying to reconstruct images, scenes and perhaps even the one or other complete dream from this.
Now take notes or you'll forget everything in a few hours. You don't need to write a full story, a few keywords are all you need.
Ideally you should keep a notepad or voice recorder close to your bed.
You might now have found some things that happen in your dreams that usually don't happen in your waking life. Apples falling upwards, writing already passed exams or winning the lottery are usually pretty good dream signs. Of course there are way more things and these are just a few examples of what could happen in a dream.
Dream signs are things that happen and only seem logical during a dream. One way to recognise that you are dreaming is to watch out for such dream signs. Thats easier said than done

If you aren't aware of your surrounding while you are awake, why should you be aware of it when you are asleep - since you think that you are awake when you are in fact sleeping. One great method to recognise that you are dreaming is to do reality checks - check, whether or not you are dreaming or not. These are called reality checks for a reason - don't just
assume that you are awake.
Good methods for reality checks are:
- reading something several times or examining writing and letters - writing in dreams is often rather unstable and you might even find the letters change right before your eyes!
- Take a good look at your fingers and count them (don't just stop after counting 5 fingers but keep in mind that you don't need to count up to 100 since having more than five fingers is already a good hint). Do this repeatedly, perhaps even think something like "I have four fingers" before starting to count them.
- Digital clocks/watches - if the watch spells "05:lol" or "23:94" or doesn't display anything that makes sense at all, you are most likely dreaming (or the batteries of your watch died - but don't just assume that, I've had a few dreams where my watch displayed strange stuff and I thought that the batteries must be bad when I was actually dreaming). Look at the current time several times. If it changes, you are most likely dreaming. Sadly it often happens to me that I just happen to look at my watch between the 59th and 1st second - which requires even more checks afterwards

So keep an eye out for anything that might be odd. Anything could be a sign that you are dreaming. If your laptop suddenly catches fire - don't just panic but also do a reality check. If Cheetah is throwing around ice cream, he has either finally snapped under all that pressure or you might just happen to be in a dream.
Realising that you are dreaming while you are in a dream is called a dream induced lucid dream (DILD).
There are other methods, like simply wanting to have a lucid dream and recognise that you are dreaming when you are going to bed and keeping your focus on that intention - or falling asleep consciously (which would then be a WILD - a wake induced lucid dream).
How can you fall asleep consciously? Keep your mind busy with something. Count numbers, imagine yourself walking up/down stairs... but also keep in mind why you are doing this. It doesn't help if you find yourself at your workplace and your boss asks you to stop counting and you comply. You could try to add "I'm dreaming" after each number you've counted to help you remember why you are counting in the first place.
This method works best if you stand up two hours earlier than you need to and then go back to bed - or if you take an afternoon nap. That's also an effective method to improve your dream recall.
While you are lying in your bed, slowly drifting to sleep, you might experience hypnagogic imagery. Your first intention might be to influence or to join in but it is more effective to just let the dream slowly take shape. Observe it and as soon as it has gained a certain level of clarity or stability slowly ease yourself into the dream. Don't force it!
You could also try to rely on external clues like lights, sounds or vibration which are either triggered by time (remember that REM starts after ~90 minutes) or by monitoring eye or body movement (you might turn around or things like that during the light sleep phase).
These external clues could manifest themself in various ways. There could be a disembodied voice, somebody could start talking to you or you might just subconsciously absorb this information. So again, be aware of strange things that might happen.
Of course, such external clues might also just wake you up.
Inside the dreamStaying there and lucid: spinning/movement, sensations, looking at the floor/hands, shouting/talking, interacting with the dream, touch!
Waking up: do nothing/ignore the dream, open eyes/move body, “kill” yourself, shout (predominant feature), focus on body/something, go to sleep (beware: false awakenings)
change the dream (different dream, escape nightmares, ...): spinning, indirect/visualisation, imagine how something would feel, door/gateway, emotion/feelings (good against Nightmares)
external influence
The power of expectations! Expect something and it will happen.
What to do / inspirationFlying: Wings, floatation, Gravity, Superman, Swimming, gadgets/tools, “light as a feather”
Confrontations: Fears, Nightmares, Subconscious, lost loved ones, interesting or historic people
Wish fulfilment: Material goods, world domination, sex, body (+RL), desires, healing, improving waking life (feeling good)
Shapeshifting: visualisation, external tools/gadgets, have somebody help/curse you, spinning, letting go, feeling
Improve waking life: training (sports), muscle memory, looking for solutions, problem solving (eg. create a lucid dream workshop), give a talk, perform in front of people – get feedback
Adventures: do whatever you want, explore the dream, be whoever you want (eg. Sherlock Holmes, Rambo, …), visit any place, … pick fights
Experiments: multiple bodies, writing, 360° vision, shadows, colour, dream-TV ? Workshop, mind-reading, telekinesis (“use the force”), controlling elements (“magic missile”), making plants grow, walk through mirrors/walls, changing the flow of time, change own body (strenght, appearance, gender), interact/talk to dream characters, “tell me when I'm dreaming”, create music, run/fly around like crazy, parcour
Save game/quicksave, shield, immortality, omnipotence
much more! use your imagination!
Have fun and don't hesitate to talk to me about such things, I love sharing experiences

P.S.: Sorry if my talk at EF seemed a little bit chaotic, I had very little sleep and a nasty headache
