This is a very quick way of making a grid of cells which will fill up an entire slide.
- Choose "Quick Grid"
- Change the number of rows/columns and local of symbol if required
- Click on "OK"
You will get a new slide which looks like this:
Click anywhere it says "Click to add text", type your word, then click on "Symbolise".
If you want to customise how you grid looks, for example have cells that are different shapes, you can use "Make Into Grid" instead.