Body turn ons

Question for both when masturbating and with your partner! 
What do you do with your free hand? (If you have one) do you like to grope your boobs/play with your nipples? Do you like it when your s/o plays with your nipples? 
  
Mine aren't sensitive at all, hence why I've actually gotten them pierced recently to see if that will help at all, plus I really like a lot of the jewelry lol. 
Any tips on better stimulating ways to go about it?