The one that works for your partner. You have to figure this one out on your own. Just don't be afraid of a little trial and error.

You should probably worship her whole body with your hands and mouth before you go down on her honey pot being gentle at the start then go with the flow. (I take it it's a women)

gently caress her neck then donkey punch her square in the back of the head and shove it up her bum.

Any non-sexual touching is my favorite. I lay my wife down blindfolded with candlelight only in our room and soft music playing, and I softly and gently touch her all over. I avoid her nipples although I come close to them a lot, and I avoid her clit although I come close to it a lot. If I take just 10 minutes doing this, my wife will cum within about 2-3 minutes of me starting to lick her pussy. It's never-miss.

lots of rubbing the boobs and licking the nipples.....and sucking on them...lots

There are some good answers here, but I have found that it varies by how we are feeling. When my gf and I are feeling romantic, just rubbing and kissing her gently, gradually moving closer to her tits, and her pussy after that, works. I move my naked body closer to her and snuggle with her. After she had each of our three children, she would love it if I would gradually snuggle up to her breasts and nurse. She found that incredibly sexy and romantic. (The problem, I say half in jest, is that I found it worked for me, too, It was incredibly relaxing and it would make me sort of sleepy. There was something about nursing from my gfd's breasts that made me feel very safe and wanted and she would hold me and I would actually get kind of dozy. So whether that is good foreplay or a better sleep technique I leave to you to decide,) On the flip side, when my gf and I are feeling more like two animals breeding in a field, subtlety goes out the window. I will lick her all over and rub my dick and balls over her and put my ass in her face while she licks it. We will bite each other a little bit - not hard but noticeable. A lot of times I will sort of push her onto all fours and mount her from behind and thrust and then get off and put my face in her ass and lick her rapidly. You can almost hardly call it foreplay. It is almost more, "Foreplay? What's foreplay?" (The role reversal, when she is feeling more dominant is also interesting.) So all of this works - but it depends on the mood. The real "best technique" I guess I am saying, is to know what mood you s/o is in. Read the signals and act accordingly.

Would be probably different for each of us. Just anticipation and knowing we are going to be with each other and taking my clothes off and getting into bed with someone pretty much gets me ready. But in bed I love being felt and fondled and played with all over and can tell when they are really enjoying how I feel to them and this does more for me than anything. One thing I think a lot of men don't realize is how sensitive our hair is. Playing with and combing or brushing my hair for a half hour makes me - well I am pretty much begging by then.