When using FormSketch, you can add text to your map by going to the menu at the bottom of the page and selecting the Text icon.
You will then see another menu pop up above it, and you can select the size of your text, font, alignment and colour.
For the text sizes, you can select between Small, Medium, Large, and Extra Large text:
There are four font styles to select from for your map:
The alignment refers to where you would like the text to align from the selected starting point that you choose on the map:
There are twelve colours to select from, and the ability to change the opacity of the text (so it can be partially transparent, or solid colour):
Once you've selected the options you want while entering the text, you can then click on the map where you would like to write and add the text.