>>4079237If you feel like you have bad control over your hand movements, here's something that hopefully helps:
1. Practice using your arm to draw rather than your wrist, more muscles are engaged and you'll have more control.
2. If your muscles are generally twitchy in your arms, training and working out, along with stretching them regularly should help keep them steady.
3. Drawing long smooth lines is really hard, I tend to break them up in smaller parts and make lots of small fast lines.
4. I don't know much about eye-hand coordination, but if you want to try you can practice playing with tennis balls. Either by throwing them at targets, bouncing them on a wall or just playing catch with your friends.
Any of these possible solutions of training yourself needs to be done regularly, for a while before the effects will show. Getting discouraged early on is to be expected, and sticking with it is hard but necessary to improve.
Being frustrated is completely normal, it means that you're failing at what you're trying to do. But it's easy to forget that failing is a crucial part of learning, no matter how tedious. When it all becomes too much, go outside and take a break, but remember to come back later and try again.