Once the beer is kegged and carbed up...sanitize and freeze a few bottles and caps. Depressurize your keg, set PSI to only enough to push beer slow. Fill the bottle from the tap, keeping it tilted as to limit oxygenation. Overfill slightly so no airspace. Cap immediately.
I've done many this way...no need to fuss with carb tabs that are very erratic at best!
You can routinely keep a few bottles and caps in the freezer for those that want to head home with one or two after a visit.
A few other threads on this if you search...others also put a small tube on the tap soas to fill from the bottom...I think this is a PITA because you need to overfill and now your trying to fill the final ounce or so from tube and not the tap itself.
Don't forget to reset your PSI to normal serving levels!!!!!!!!!!!!!!!