This completely depends on the person your asking! If it’s with your partner dont make it about a specific person, make it about the experience you can share together. Your partner will not want to have a threesome with someone they think you have a crush on so try to choose someone neutral or even someone you don’t know. Always pay attention to both people in the threesome equally, maybe just a little more to your partner. Make them feel special by making eye contact with them even though you might be fucking someone else. Make them feel as comfortable as possible and you could find yourself having alot more threesomes!