How can an eligible voter be sure that he/she is duly registered?

The Electoral Commission uses the Photo-bearing register. This means that only people whose photos have been taken by the Commission can be sure that they have been registered. 

Therefore it is very important during display periods to go to the Voter Roll/Register display centres where you registered from and Check to see that you are on the register. If you are not launch your query through the display officer with the details of your registration.

There is also an online link http://www.ec.or.ug/register which you can use to check for your registration details