Generally, people can manage to get sexually excited without their partner doing anything - especially if the relationship is new. Different things turn different people on, and if your boyfriend is making advances towards you....holding your hand, kissing, or more... it means he finds you attractive.
Just from you being you.
If you want specific techniques, try paying attention to what seems to get him excited now. His thoughts will come out as actions - leaning closer into you, changes in his breathing, etc. If he likes something now, keep it.
If you've been together a long time and want some new ideas, try asking him for things he'd like. Most guys would jump at the chance to tell their partner what they like!