Use emoji in your slack convos, have regular non work related chats, learn about your colleagues hobbies. Basically, really try to engage in the same types of things you would do in an office, just adjusted for your remote tools.

I have found that if I put in some real effort with interpersonal communications and relationships, the work experience is an order of magnitude better. Then things like code reviews, backlog grooming, etc go a lot smoother.