Sniper tips: aim for where they are going. it is the best when they r jumping since it is obvious where they r going to land. But just look for ur opponents' moving/strafing patterns.
BR tips: Pretty much the same with sniper. Just aim around their head, the cross hair will have a dot in the middle whenever it is a headshot. Never stop shooting a BR until ur opponent is dead, it often panics ur opponents. BR can finish ur opponent in about 4 headshots. Try to combine BR with grenades, bruteshot, or plasma pistols.
Shotgun tips: Dont take out shot gun until ur opponents get close to u. Ur opponent wouldn't come near u if they see u carrying a big bad behind looking gun. When ur opponet get close, aim at their mid section not at their head.
Bruteshots: One of the harder weapons to aim. Aim at the ground infront or the wall next to ur enemy and it will bounce into him.
Rocket launchers: Dont aim at ur opponents, aim at the ground/wall/obstacles around him.
Heres a dual weapon and combo chart i made:
Dual:
plasma rifle+SMG"short range"3/5"good in team & FFA"
plasma rifle+pistol"short range"3.5/5"good in team & FFA"
plasma pistol+SMG"short range"3.5/5"good in 1v1"
plasma pistol+pistol"short range"4/5"very good in 1v1"
needler+needler"short-medium range"3.5/5"best used in open field"
needler+anything else"short-range"0/5"just stinks, dont ever do it"
Combo:
plasma rifle+BR"short-meduim range"3.5/5"not good as the next combo"
plasma pistol+BR"short-medium range"4.8/5"very effective"
bruteshot+BR"short-medium range"4.5/5"easy to hit/ huge splash dmg"
sniper+BR"medium-long range"4.8/5"can be amazing if u can aim"
sniper+sword/shotgun"short/lon... range"/4.8/5"good for 1v1 & team"
plasma pistol+shotgun"shot range"2.5/5"good for fooling around"
sword+BR"short-medim range"4.5/5"almost invincible"
Also dont forget to BXB when u r close up.
Basically just practice and fool around with all the weapons and see how each works.
Add me on live if u wanna play against/with me. Gametag:SLY3R