Interchange. take the consideration of how you are going to use it.
it works well with stuns and units, try the famous combinations of lasso bolt root firebolt and few others together with creeps or even foots.
learn how to use it properly to deal even more dps, simple tips like:
have you got your creeps/units ready when you interchange? perhaps you could also use the firebolt from the frost towers for even longer stun and dps.
you should think over your positioning when doing that, basically if you gonna keep dying because of the poor choices of interchange and swapping kills for deaths it ain't gonna work.
just remember, anyone can break your roots with a teleport, this way they loose gold but you on the other hand could get killed as well and most importantly you aren't getting feeded and that's not the point.
learn the proper combinations and order of your spells usage so you will deal the maximum amount of damage with one huge stun and hope to kill the hero before he runs away.
