Making Incense, but not sure how to get the effects

[Jobe00]

A friend running a PF1 campaign gave the party three blocks of incense that once you meditate for 8 hours and prepare spells or regain your spell slots, you gain a +2 alchemical bonus to Int and gain +1 caster level for 24 hours.

I know this is an activation, but how do I do the eval script to get the bonus when active?