What are things a girl can do when a guy wants to take it slow. Like what could she do to honor that but make progress as well?

Well this is a wide open question. It depends on your age, what you are trying to take slow, and a question you should be asking yourself how much do you like that person. Pressure can lead to a lot of terrible things in a relationship. Taking it slow shows a lot about a person. It shows that you know what you want and your willing to be patient with it and let it happen so the mistakes are few and far in between. If they can't wait then they aren't what you want and should feel happy that you didn't bend to please them. Relationships are a mutual thing where both parties are on the same page. Sometimes it feels like it will never happen, that just means your looking to hard. There are a lot fish in the pond and when you stop trying so hard that's when it will happen.

Though if you are sure he is the one, all you have to do is reinforce his love for you. In other Words more dates, more interactions that build the relationship like doing things together family get togethers going to each others events supporting them. If you find that is too much then guess what your not digging him and the same goes on the other side.

If you want to take it slow for other reasons like you're getting over a relationship, he is friend first, you're in a relationship then you should probably tell him not right now and explore other venues.