My philosophy is very simple: you don't need to spend a lot of money to keep your horse healthy and safe. Keep it simple and avoid all the "bells & whistles" that everyone trys to sell you. Stick to the basics.
Choose a horse that's the right size for you.
Now days younger people sometimes feel pressured that they have to show their hourse. This is fine but do it only if you want to.
Take time to train yourself before you try to train your horse. A few hours of bad training will remain with your horse indefinately.
Listen and watch others, learning is an ongoing never ending event.
Get to know your horses every move, every muscle flinch, be one with your horse, not against him or he against you.