There isn't much you could do unless you swap out Snore and/or Rest for something else.
You could try one of these sets:
Milotic @ Flame Orb/Leftovers
This you can deal some damage in Scald and Ice Beam then tank it out with Rest or Recover all whilst Toxic slowly eats away at your opponent.
You could also go with this:
Honestly you're good with whatever you choose at the moment, it all depends on what you're aiming to do.
Hope I helped!