Hi! "Di solito" e "solitamente" mean pretty much the same thing. ex: "lunedì di solito vado al cinema" "lunedì solitamente vado al cinema" both sentences are correct. same thing with "di norma" and "normalmente". You can choose whichever you prefer.

the only difference is that normalmente is an adverb and solitamente is an adverb as well....as you may already know -mente at the end help you to discover the adverbs...and as the name adverb suggest they stay near the verb :) the meaning, like Martina said is the same

I agree with martina :)

In genere io uso una di queste due espressioni: a) di solito b) in genere {Di solito, in genere} alle 5 del pomeriggio se sono a casa prendo un tè (tea).