Take as much marzipan as you need. For "baby" size carrots, I use 5 grams of marzipan for each carrot. For larger size carrots, I suggest 10 grams of marzipan for each carrot. Multiply the number of carrots you plan to make by the weight of each carrot.
Knead the marzipan to ensure it is pliable and smooth. If it is too sticky, knead in a little confectioner's sugar.
Add orange food gel, one drop at a time, kneading in after every drop until you obtain the desired color.
Weigh out the amount you are using for each carrot.
Using the palms of your hands, roll each portion into a ball and then into a log, bearing down on one end to make it thinner than the other end.
Use a toothpick to insert a small hole on the top of the carrot. (You will insert some green marzipan into the hole to look like the leaf.)
Use a paring knife to gently mark grooves around the carrots (circuling the carrot) to give impressions around it. Be careful not to cut into the carrots. You just want to make impressions.