Ah, well as I am a switch....I like to be the spanker and to be the spankee, lol. So it really depends on what my partner wishes. But prefer the light and playful to just verging on 'oweee' instead of the really heavy stuff. However, if you want stripes, I've done that too per request.
Slow with a lot of affection and rubbing the area between pops (I mean pops on the bottom!). And then as the excitement starts to climb, more force until the squirming starts ... and each person is different to what they desire.
I have found, for me, one little pop on the bottom is fine but it's really not enough in terms of a "spanking". That's just some lovin' pats in the moment of passion. Spanking does leave some pink, or welts, that generally fade pretty quickly and leave the bottom feeling nice and warm.
It's not for everyone but it can enhance the sensation of sex.