If I can't get a skill and get frustrated, I go and get a drink, then visualize myself doing the skill perfectly. I have to try not to say things like I can't or picture myself falling, getting hurt, etc. because then it just makes everything harder.
If I have a bad practice or meet I try to forget about it because I know that I can't change what happened but I can go back to the gym and work hard to fix my mistakes I have made. My main focus is staying positive!
There's always something more. Whatever you're frustrated on now is only a miniscule fraction of your gymnastics 'career', or even your life. Looking at things in the big picture helps me relax.
I'm also really involved in charity work, so that has helped me with that principle. It sounds like a guilt trip, if it's something you truly feel right down to your core, then it's not. When I was irritated with my front tumbling pass or giants or having a bad meet or whatever, sure I would be upset, but I would catch myself, saying things like; wow I'm in a nice facility with coaches who care about me and when I go home both of my parents will be there to ask me how my day was. I can take a warm bath and listen to music before bed. I know I'll be safe in my bed that night and when I wake up in the morning,I can eat breakfast and I have the privilege of going to school and getting to do it all over again. We take a lot for granted here. Not being able to nail your tsuk every time is not that big of a deal.
I'd like to stress that I'm not perfect. Sometimes I do want to feel sorry for myself, but I can remind myself how lucky I am to even be able to feel that disappointment and it motivates me to do my best for all the people who don't get that chance.
Whenever I am frustrated and not happy, especially after trying a skill about 6 times in a row...I have a calming ritual, I take a deep breath, close my eyes and turn all the frustration into a driving need to get it right, focus my mind on all the aspects of the skill and finally, tap my wrists together. that last part is the " I'm ready to rock and roll" symbol that means I am going to kill a skill. all in all, it is a pretty intense moment!