HI Medha,
How many employees do you have ? R u going to have Indoor or Out door games. If out door then you can hire good play ground and have Athletics ( 50 mt, 100 mt, sack race, even 400 mts)for both men and women, Cricket, Football for men , some team games for women such as hand ball so. You can hire the Umpires from the ground it self, they will help administering the games. You can do the following to organised a good Sports Day.
1. Book a good Sports Ground
2.Decide on the events individual , and teams yu want to organised.
3.Make Teams
4.Give diffirent t-T-shirts or Caps for identification of teams
5.Select a Caption and Vice Caption from each team.
6.Have a meeting with all Captions and Vice Captions and give them the list of events, rules for each event etc,
7. Take the participants name for each event , take care that there is no repeat participant .( most of your employees should participate in the atleast one of the event)
8.Announce the schedule of events atleast three days in advance and put it on the notice board.
9.Make arrangements for Umpires or refrees either internally or externally ( if ground provides well & good). If it is External the results will be impartial and your all employees can take part in event.
10.Give good prizes such as Medals for individual events and Cups for team event. Make a point system for each event, and the team who scores maximum points can get a Shield.
11. keep some light snacks and lot of water.
One thing is sure it takes a lot of commitment and efforts from the organisers, but its worth doing.
I hope it will give you some idea. If any qurey do get back to me.
Cheers,
Harshad