[threesixandnine]

One of the ways is to manually split indeed.

Although I must say that natural swarms show greater vigor when building new comb than splits. Even packaged bees built faster than splits. That is of course my experience and you have to keep in consideration that I didn't add any foundation to new colonies so that was maybe one of the reasons. I let them build their own comb on a narrow strip in the frame/top bar and never tried with full foundation.