It's a good idea when you're first trying to master sugar paste roses to use a paler colour as this will be easier to mould. The darker the paste the more food colouring used which makes it harder to mould.
Begin by coulouring your sugar paste with food colouring paste, liquid food colour may make the paste too soft. Knead the sugar paste to make it pliable, if you find that it is too it bceomes too sticky, dust your hands and work surface with icing sugar. If it begins to dry add a tiny amount of white vegetable fat.
Take 40g roughly of the sugar paste, split a polythene bag open and place it on your work surface. Take a third of the sugar paste and roll it into a ball in your hands and then into a cone. Flatten the base on your work area and then indent it so it looks like a cone on top of a ball.
Next shape seven or eight balls from the rest of the sugar paste and leave them on one side of the bag. These will form the petals. Fold over the other side of the bag and flatten each ball until thin. Taking care, peel back the bag and take one petal at a time, mould it around the cone. The first petal should fully cover the cone. Take the second petal and fold it over the seam of the first petal and then mould it around the cone. Place the third petal opposite the second and then tewak out the petals to make them look like real rose petals.
Finally, fold the rest of the rose petals around the rose petals in the same way, each overlapping the seam of the last. Keep tweaking the petals as you work and with a small knife, cut away the base of the flower at a slight angle.