Ordinal Arithmetic and Cantor Normal Form

[runnnincircles]

I am studying for a final exam in set theory and one thing I know I will need to be able to do is rewrite expressions for ordinals in cantor normal form, however my book doesn't give any concrete examples and I am having difficulty finding examples with worked solutions online. I was wondering if someone could explain the steps for putting the following into Cantor normal form (these are taken from old exams provided by my professor):

a. (ω3+ω4⋅2 + ω)⋅(ω6+1)
b. 16⋅ωω+ω5+ω