Let me know if I am incorrect in doing so but I kind of separated the process and made it longer to help myself better understand. Meaning in my head I thought of De Morgan's law as being the "negate" part of the contrapositive process "flip and negate". Flipping the conditions is the first step, and then to negate using De Morgan's law is the second step. I still ended up with the same answers. Not sure if this was obvious to everyone else but going about the process in this way helped me understand better.

Negate a Conjunction

Initial conditional statement:

M→N and O

↳flip the two conditions:

(N and O) → M

↳conjunction (and) swapped for the disjunction (or):

(N or O)→M

↳ Negate each the conjuncts:

/N or /O→/M

Negate a Disjunction

Initial conditional statement:

/N or /O→/M

↳flip the two conditions:

/M→/N or /O

↳ disjunction (or) swapped for the conjunction (and):

/M→/N and /O

↳ Negate each the disjuncts:

M→N and O