Combine flour and salt in a medium bowl. Slowly stir in the oil, warm water, and 2-3 drops of food coloring until the mixture is well combined.
Transfer the dough to a flat surface and let it sit for a few minutes. It may feel a bit sticky, but DO NOT add more flour. As the dough sits, the salt will absorb the extra moisture. Knead well.
If your dough is sticky after about 5 minutes, add an additional 2 tablespoons of flour at a time until it is the perfect consistency.
HOW TO STORE YOUR DIY PLAYDOUGH: Store in a zip-lock bag or airtight container, and place in the refrigerator. If you notice the playdough getting a bit dry, you can add a few drops of water and knead that into the dough.