You require a visa to enter Uganda. Your passport needs to be up to date and should not expire within six months of departure from the country.

For the soccer academy you will require:
Football boots, 
Kit
Training resources
Coaching programmes
Footballs

On more general matters you will require:
Open shoes
Raincoat
Few cotton T-shirts (that can also be bought locally)
Sleeping bag
Mosquito net (25 degrees centigrade at night)

Further information will be passed on to you at the pre departure briefing.