Hope this is the right are for this question…
I’ve been journalling my dreams more or less regularly for about a year.
By now I’ve seen certain patterns occur regularly, certain people I encounter, activities like sports and other specific settings.
Now I’m wondering how this information can help me become lucid.
These signs are not unusual themselves unless I compare them to where I am in my waking life - I don’t see these people in my daily life for example.
So how do I use this information?
What I’ve been trying to do so far is to ask myself regularly, “where am I, who am I with, how did I get here?”.
Any advice?
Thank you in advance 
Those questions you have been asking are great. Those are mental reality checks that make you pay attention to the world around you just like any reality check. Being more aware of everything happening around you like that will eventually translate into questioning your state in a dream.
The point of those dream signs is to get you to reality check whenever you come across it in waking life. If you dream about trains, then you would RC when ever you see/hear one in waking life. The idea is to make it a habit so that you do it in a dream eventually.
I haven’t found many good dream signs myself, because my dreams tend to change faster than the RC becomes a habit. Lucky for me, I dream about fiction a lot, so just connecting “That’s weird” to “I might be dreaming” has been working for me.
Keep doing those mental RCs, keep your awareness high and use autosuggestion. Perform WBTB and tell yourself: “I will become lucid”. Those are my tips.
Thank you very much for your answer, Letaali!
I actually managed to become lucid last night, which was not directly linked to my Rcs though.
What I realized is that I do get into situations in waking life where I get in touch with my dreamsigns, just not as directly as I expected. I’ll keep doing my Rcs in these situations and see how that’ll go!
Congrats on the lucid dream! 
You don’t necessarily need your dreamsign to occur in waking life to perform a RC. If you know what your dreamsign is, just commit it to your memory and tell yourself that next time it happens you will RC.
For example, a dreamsign for me that only happens in dreams is peeing for an incredibly long time and still not feeling relieved. All I did was make a mental note that this is a dreamsign, and next time it happened in a dream I remembered it was a dreamsign and became lucid.