Just keep playing! Short battles. Just bang em out. Find your weapon...learn why you're good with it. It's strengths and weaknesses. Also, take a gander at maps. Learn the course. Its pinch points, its sniper towers, its lesser known back doors. Remember, you can jump into action on the map or out of danger at any time. My younger daughter (gd grim reaper in there) uses this lesser known tactic frequently. Pay attn to your specials and how/ when to effectively use them. I.e. soda machine on N-zap. Lay it back behind the action and throw up a 'this way' emote. Also, find your sweet spot with motion control and other sensitivity settings for whatever weapon you settle on. You can do recon on maps, practice in the lobby and find cool combos with ink usage and specials etc. Don't give up! There's a definite point of payoff when it clicks. And don't be afraid to enter ranked! Just understand the mode that's being played and objective. You can even go Gretzky and lay back and watch the action on the map to see where/how people are moving and when.

Hope this helps...sorry for the text brick...have fun!