Hi Mandeep,
I sugeest make a movie contest. 20 members can be divided into 4 teams.
here, you give them 1 newspaper, 1 chart, 1 Scissors, 1 fevi stick. Time limit - 15mins for the each team
Team had to thing on the concept, select the pics from the paper cut & past them on the chart in a sequence and each team had to title the movie and after 15mins they had to explain the movie with the sticked pics on the chart.
This is really Fun. Try out.
you can go for a Ramp walk, ask all the team members to come in Ethnic wear.
Gifts can be cups, show items, scented candles, being diwali time you can gift nice diyas to them.