I would consider which hotel it is & what sort of people get married there. I do fayres & pick very carefully because certain hotels have a certain type of clientele & this obviously determines their budget etc. Also make sure the hotel / events company will be promoting their fayre on local radio / newspapers etc because otherwise they tend to be very quiet & not worth the effort.
That aside, I do little demos, offer people hair or make up & just do a simple hair up or if I'm doing makeup then just (for example) eye makeup. Make sure you take someone with you because you miss the opportunity to talk to brides whilst you're doing a demo.
I also find that people tend to visit wedding fayres well in advance of their wedding so they tend to be marrying 2 or 3 years down the line. I rarely get any bookings out of them for weddings in the next few months.