An important tool to have when competing in pageants is a photographic portfolio, basically a model portfolio with some pageant specific shots included.
Modelling work, both catwalk and commercial, is an important part of what is expected of the modern day beauty queen. This is why pageant management and, sometimes, judges, want to see what a contestant looks like in pictures.
It is very important that the pictures actually look like you, so the viewer can recognise the person standing in from of them in these.
One fantasy or glamour shot is OK, but the images should not be edited within an inch of your life. If you end up looking like Barbie, plastic skin and all, you are in trouble. As a photographer you learn that agents and advertising execs want to be able to see pores in facial pictures (unless you really have no visible pores).
Particularly swimsuit shots should be true to your figure, as people working the fashion industry do not like surprises. So, please stay away from photographic diets.
Important is not to only show different looks, from very casual to glam and everything in between, but also different expressions. Give evidence that you are a brilliant photographic actor.
Lastly, decide in advance if you want a colour or black+white portfolio. Having a mixed portfolio is not deemed professional. My advice though is to go with colour for your pageant portfolio.