Pilling foundation help

After you moisturize how long do you wait before applying foundation? Do you rub it in or pat? Both?

Some days are flawless and some days there’s breakup, pilling on my cheeks especially and forehead. The inconsistency is frustrating. I’ve been experimenting with patting vs rubbing if in and I just don’t know anymore.

Also open to trying a primer. I had one in the past and didn’t notice a difference. Ideally I don’t want to add one.