I forgot that some guys equate simulators with actual flying -

I find sims tooooo forgiving
anyway - single roller - try making a four point roll into a circle -get used to seeing attitudes
Once this is comfortable - figure the blending inputs for your plane -(or sim) they are not all the same -by a long shot
for really getting totally comfy with inside outside rollers - practice a big flat horizontal 8 with four rolls three rolls etc..
Getting good at this stuf is like learning to play a clarinet - you have to practice and try sequences which are more difficult than those you already know OR wish to learn.