You can use a table, as you said. And yes, there are some spectators who wanna spoil the suspense and just look at a card or something. A few ways to tackle this:-
1) Continue smoothly with your patter...sometimes we magicians do think too much and get all critical about "Will they examine this?" or "Will they want to check that?". But most of the time the audience does not do that...in fact they become spoilsports very rarely. So relax.
2) Say you handed a different card from what THEY think you handed them. Always convince yourself that you have handed them the original card. If you believe in it, the spectator will too. You will have said a VERY convincing lie.
3) Maybe your style might not allow it, mine does. Sometimes when the trick is moving towards a dramatic moment, I tell them "Do not turn over the card, it will be sorta anti-dramatic" and they accept without being suspicious. Just ask for what you want.
4) Having a test subject always helps, so first practice it thoroughly with a table and go on to a test subject, so you don't really expose the method and even if the trick fails, remember, more often than not, it must have been your behaviour that made them check the card.
5) Sometimes I just bite the card between my teeth except handing it out. Won't work for all tricks, but looks cool.
;-)
