Hey man you would get a lot more answers if you posted this in this section.
And you can only do so much without getting actual training. When I was doing boxing, I used to grapple a lot and I got alright at it. But when I started taking BJJ classes, I found out that I was doing a lot of stuff wrong. I would definitely try and get some kind of training if I were you.
For the time being, just make sure you maintain good cardio and stay disciplined in your training.
Have fun and good luck!