Most Helpful Guy
There's a difference between attached and being clingy. You don't sound like your relationship is unhealthy (clingy), so I don't think you have anything to worry about.
If you're looking for gestures, the most meaningful, in my opinion, is when someone either supports my interests or fulfills my needs without being asked to do so.
Think about what he likes and buy him something small and practical that shows you support him in that. Don't try to be elaborate. Something small and modest is best.
Or maybe he complains that he needs to buy a new belt but he (all men) hates shopping for clothes. Simple.
Maybe he has a favorite beverage. Have some waiting in the fridge for him when he comes home. Or cook a meal you know he likes.
Don't do all these things all the time, but surprise him with something once in a while and it will go a long way.
Most Helpful Girl
Very little would make you look clingy or annoying unless you go absolutely crazy and/or your boyfriend is completely detached and lacks any sort of emotion.
This goes for pretty much anyone in a relationship:
- Just tell them "I love you". Pretty self-explanatory.
- Listen to your partner and show them that you've listened by remembering things they've said.
- Do things for them. Bring/make them soup when they're sick, help them clean, give them a massage after a long day at work, help them de-stress by doing something fun or relaxing, leave little notes for them, buy them a small gift that reminded you of them, etc.
- Support them. If they're going through a hard time, let them know that you're there for them if they want to talk about it, or that you don't even have to talk, you could just hang out and do something nice if that will help.
- Personally I love baking, and my boyfriend loves sweet stuff, so I sometimes bake for him.
And so on. Should be pretty simple stuff. Like you don't need to hire a pilot to spell it out for you in the sky.