Anniversaries, dating or otherwise were invented for this reason.
An anniversary should be a day when you conveniently forget about the rest of the world, and focus on each other.
If you know his favorite meal or desert perhaps take him out to eat at one of his favorite places which is known for that food type. Many guys fall into one or more of the following categories: Do you celebrate a second and third month anniversary? I would have a conversation however so you don’t have one of the partners expecting a gift or recognition event on a monthly basis and being disappointed when it doesn’t happen.
If you can’t get this detail worked out in a mutually agreeable manner you probably won’t have to worry about celebrating many monthly anniversaries anyway.
Some gift stores and websites have created their own lists of suggestions but nothing as widely recognized as the wedding anniversary symbol list first created by Emily Post in 1922.