How do I switch out Wizard spells in spellbook?

[gasguy192]

Hi.
I bought a spellbook, in my gear.

During character creation, for Level 1 Wizard, per the CRB pg 204 I start with my choice of 10 arcane cantrips and five 1st-level arcane spells. That is done, they show in the spellbook.

And then for my daily choices at 1st level, I choose to prepare two 1st level spells and 5 cantrips. That is done. (But I really don't remember how it was done).

Now... how do I switch out spells/cantrips for my daily choices? I can't figure out how software to do this process... am I editing the spellbook? (that doesn't seem right), I have to edit my spellslots... where do I do that?

Thanks for any advice.