I've got a few to add to this list which have been given to me over the past years and some will be repeated over again but ah well.
1. Practice, Practice, Practice. after all practice makes perfect but only if you are doing it properly.
2. Spares are everything, strikes are just there to add bonus to your game.
3. If you don't enjoy the game, stop playing it until you regain the confidence you once had when you first started playing the game.
4. Don't talk, just listen and learn by watching other people play their shots but don't copy them.
5. Don't let your frustrations get the better of you.
6. Always take your time when you get onto the approach, there is no need to rush.
7. Stay focussed when bowling in league, tournaments and in practise play because if you muck around, you won't achieve anything and will only make you bowl worse.
8. Have fun, after all, it's just a game.
9. Remember the three R's:- respect for yourself, respect for other people and take responsibility for your actions.
10. Look after your equipment, you don't need to buy a new bowling ball everytime you go to a tournament. Not that it hurts to upgrade to a new bowling ball if you really need to, just don't get into the habit of buying a new ball for every condition you may play on. What you have now, will probably do the job if not better, you just have to make the adjustments.
I think that will do for now.