Use the Windows file explorer to copy the desired sequence database(s) to a floppy/zip-disk/etc to be transferred to the other computer.

If you've just written a few sequences in a temporary database, you can copy the database to the other computer, then use the 'Sequence | Import Sequence(s)' function to import the sequences into an existing database.

I use several computers. One of them I designate as the 'master' computer. It contains the current version of all my sequence databases. Whenever I write sequences on a different computer, I make sure that I copy the sequences to the 'master' computer. Then, periodicially, I copy all sequence databases to the other computers to make sure that they are up-to-date.