Make it exciting!
See if you or your partner can have multiple orgasms.
Read erotic stories to each other out loud.
Give each other a sensual personal massage that turns into a sex session.
Use a lube to add a cooling, warming, or pleasantly tingling sensation to your genitals or nipples.
Get wet and wild with shower sex.
Send texts to one another all day long as foreplay.
Try to go a week without having sex, but do tease one another throughout that time.