Sounds like you are grinding. Don't. Having to redo it so many times and not making progress is probably a big factor in you feeling impatient.

In my experience patience comes from two parts. Part 1 is earned through practicing being present in the moment. Part 2 is earned through the pain experienced from impatience. Both are built up through mileage but the better you get at part 1 the less you have to rely on part 2.

Collect music that helps you focus. I find chill music without lyrics helps me the most. Or songs where the lyrics are very subtle or in a different language.

Practice "rituals" to help you get in the right mindset. The way DAB suggests to do your warmups and has you use a ruler to make the frames/layouts for your warmups.

Work in an area that isn't distracting and doesn't get in your way or frustrate you.

This double-inhale technique helps me destress and lower anxiety which often coincides with impatience in my experience.

I found drawing alongside people in comms on discord helped with following the 50/50 rule.

I hope this helps!