How to tell him I miss him?

At 23 I will admit to only being in 1 prior serious relationship and a total of 3 relationships all together.

I'm inexperienced with all things love; I know I'm in love with my boyfriend and I know that although we live together I miss him when he's not around.

I'll send him "I miss you" snaps and tell him in text but last night he told me I'm doing it wrong. How?

He said I need to figure out how he likes seeing that I miss him. What does that mean? Does he want sexy seductive pictures and texts of what I'd like from him and in other ways of "I miss you, when will you be home?"

I need advice please ladies. I'm embarrassed just admitting my lack of experience here. It's bad enough sexually I'm still learning with him, but now I need to learn how to show my affection better?

This is hard 😂😂