Practice makes perfect. What made me better was always verseing my friends. Also gather a team when you go into multiplayer, teamwork is essential. When you go in alone you get stuck with 3 randoms that tend to rush in by themselves and die. Get your friends and communicate. Always let them know where the enemy is and if you need help. That will make all of you stronger together.
Snipeing wise (this will also teach you how to control your aim) Start a custom game by yourself on The Pit. Look up when your near the sniper platforms(above where sniper spawns with lift) When you look up you will notice little yellow moving birds. Snipe them. One shot will kill them. It's hard at first but its the fastest way to learn how to control your aim. I did it, I still do it. Good friend of mine taught me that. Now I beat legit generals without a problem lol.
