At this time, all our collections are created and managed by the marketplace admins, so you cannot specifically add your product to a collection. You can, however, check to see if there is a specific collection that maybe you want to see on the marketplace by scrolling through the collections made here:
An easier way to check is to run a search and if there is a collection it will be listed on the left side of the search while on the right side will be a list of items.
If we are missing one you think we need, we would be happy to add it. There are a million combinations of how collections can be created and we are happy to build another one if it seems to be a fit.
We typically shoot for things like 1957 Topps Baseball Cards, or Joe Montana Football Cards, so please keep that in mind.