This depends on your preferences and what feels natural for you. You can make offerings on a schedule if that’s what you prefer (like once a week), or you can make offerings whenever the mood strikes. I personally make offerings whenever it’s a holiday, whenever I make a special dish, or whenever I feel like sharing the yummy food I have with the entities that matter to me.
Heathens will sometimes choose to make offerings to deities according to their corresponding week-day, which are as follows:
Sunday – Sunna
Monday – Mani
Tuesday – Tyr
Wednesday – Odin
Thursday – Thor
Friday – Frigg / Freyja
Saturday – Free Space!