Find your shade
Squeeze some pink colouring (about the size of a 5p coin) into a small bowl, then squeeze a third of that amount into a separate bowl. Add 1 drop of vodka (or water) to each bowl. Dip a paintbrush in water; dab with kitchen paper to remove excess. Use the brush to swirl the colour around to water it down; repeat with a clean brush in the second bowl. Test on a spare piece of fondant and add a little more water or colour if necessary.
Opt for a medium-pink for the flower and a very pale pink for the background. Testing on a spare piece of fondant will help judge whether to add more colouring or water.