1. dont use double fell cleave whenever its available use it always with berserk (if u can use full swing u can add it for more burst) when burst is needed and try to line it up with internal release
2. use storms path against enemy burst and storms eye for slashing debuff
3. use unbuffed fell cleaves on boxes to prevent the other team from getting it

Tbh its easy to do alot of dmg but its very situational so your burst dont go to waste. You should practice and learn with each match high dmg doesnt mean much in the end it always depends how u used it and against a sch you will also be lower on dmg than usual.