Right, now for colouring fondant. Firstly pick a gel colour. As I've mentioned before, only use gel colours for colouring fondant as the water based colours mess with the structure of the fondant.
For this example, I have chosen "Poppy Red" by sugarflair as I am aiming for a pink. You can add more of the gel to get a stronger colour, but to get the bright or deep colours you may want, I would recommend with buying the pre coloured fondant or add some to the fondant, and the paint a layer of the colour over the top to achieve a darker red.
Take your fondant and add some of the gel with a cocktail stick (don't add a lot otherwise you'll get more on your hands than on the icing!
Now you will need to knead the fondant until the colour is incorporated.
Warning - your hands do get stained and it is hard work!!
It does get a little streaky, and I would recommend adding a little more colour at this point (again to save your hands ffrom the start)
As you incorporate it more, it will look a little marbly, which is ideal if you want to add a marble effect to your cake.
After a while, it will become the same colour all over. As I said, I was aiming for a pink, so this is how I've left it.