It took me a long while and I am still not very good if I am honest. If you are really struggling let the tyres down a bit and it is easier. As you get the hang of it pump them up again. I used to put the tront tyre up to a solid object at a slight angle then pull the bike upright with the bars. At first I could get the tyre 10-15mm off the object but after a while it all sort of comes together. Lots of practice, often and not for too long.
Sometimes looking at the wheel is best sometimes looking into the distance. Try both, alternate. It will come eventually - took me about a year. When the engine is running it is easier so more time you can practice with the engine off the better. I find it easier pointing down on a slope - no idea why. I try to stop - if on a trial and need to balance - when pointing down on a slope...