I dont even know where to start…
pick a mount that you like. play with it. try some new stuff. It took me a while to even make up 1 trick, so it takes a little while, but eventually, it will come.
Well the best way to start to making tricks is by learning tricks. The better player you are the easier it will be to make them. Also, you should start off with trick variations instead of entirely new tricks.
Like he said pick a mount, maybe double or nothing (easy to start with) just try hoping on to other strings, swinging around in and out of different openings, coming from the back…
Think of things you have done in other tricks, granted dont steal the trick as your own, but little techniques, try to incorporate those.
Just play around, making tricks to me can be more fun than learning others tricks 
Don’t be afraid to get a knot. Just mess around. Throw the string where you normally wouldn’t, and hop or move the yoyo to somewhere where you’v never thought of. Do things in mounts that you would normally do in other mounts. Believe it or not, I’ve come up with some of my favorite tricks not looking at it. Just try anything and everything, and remember to have fun! ;D
Get inspiration from other players. Pay very close attention to how other people’s tricks are structured. Like everyone else is saying, try different things that you haven’t seen/ done.
Learn to pop the yoyo. That opens a lot of opportunities.
Copy pasting something I told someone else that asked about Trick Development.
First, I do have to say that being new for only a few months is a major disadvantage. Usually beginners need to build their base before they even consider trying to explore making their own material. It is crucial to build the base by learning all of the main tricks on tutorial sites like Yoyoexpert. This will give you a good perception and depth on tricks.
Creativity is something that cannot be forced either. If you try to force yourself instead of smoothly trying to make a trick, you will get frustrated and angry at yourself and at yoyo.
First step:
is usually taking a element from somthing you were interested in. Whoever you look up to for yoyoing, watch their videos, perhaps strip them off youtube so you can watch them frame for frame. Pick a good element you like and learn to get to it.
Step Two:
after you have learned the element it is time to experiment/expand on it. Experimenting with the mount or element is usually by trying to twist it a different way. Perhaps trying to get into the mount or element differently. This is done by purposely failing at the said mount. Failure at doing something your own way can actually lead to interesting results because it can lead to something completely new to you.
Step three
After you have created a nifty new mount or element you are confident in. Make sure to do it two or three more times in a different way. This allows for variation and you can eventually pick the best element/trick/combo.
Step Four:
Sit back and feel a bit of pride for creating something that to you, is new.
Here is the thing about tricks that you MUST understand. Almost everything out there has been already done by someone else. But it has not been done BY YOU. So when you do develop tricks, if people give you crap about it merely ignore it while also merely nodding to what they say. Sometimes if we make something and get hyped for it we may think its new but the idea is not. HOWEVER EVERYONE DOES TRICKS DIFFERENTLY, even if it is the same trick. This allows for countless variations of things.
So to go over this:
1)steal a concept
2)learn the conept
3)mutate the concept via failure/experimenting.
4)master the new concept.
5)voila new stuff for you to do.
Not too hard, but a lot of it seems to be how people feel good about yoyoing when they get compliments from their new stuff. Yoyoing is about self expression but also inner satisfaction. I look at yoyoing with a Artist mentality. We all create something with the toy connected to the string. Its up to you to decide what to do with it.
Sorry if I am no help and if you ask me anything about competition type tricks I am the wrong person to ask.
try doing a trick in a different way like under the leg 
Be patient with knots. Try mixing some crazy tricks you know together and like yoyomaniac123 said, do some stuff behind the back or under the leg. There’s a zillion different possibilities while you hold that yoyo in your fist.*
* Get a Spin Dynamics Monkey Fist, they rule!