I was wondering the same thing "Pantufla..."
Thus, the simple, direct answer to performing w/out a table (per Mark @ PM)is "You COULD spread the cards in your hands if you're comfortable with that. It just requires an extra bit of care."
Mark adds "The table is preferable, however. Especially if you're doing the card to pocket version because you'll want the deck out of your hands when you're revealing the card".
In conclusion...a table is better.
Hope that helps.
Kudos and many thanks to Mark @PM chat...