I find a lot of good spots that are subtle, are light touches around the inner joint around the elbow, along the jawline, and around the small of her back towards the center. Less subtle is the back of the knee. I also found that use of light touches with the very tips of your fingers in the right places around her face, neck and shoulders in a smooth motion can be very effective if done right, but if done wrong can be a gambit because if you aren't good at it or if she's not remotely interested this will not work for you.
For a good turn on that is pretty much universal, try kissing a girl around under her chin and jawline, her neck and this one sweet spot that is located around the hairline slightly below and behind the earlobe. Light kissing, biting or tugging of the dangly bit on the earlobe are also pretty good on average. While spending so much time around her ear you may find that your breathing can be a real turn on. Keep it in mind.
Anyway that's what's worked for me in the past. Good luck.