Quick Tip: How to Grow Thicker, Longer Eyelashes Naturally There are a lot of products out there that claim to make your eyelashes grow thicker and longer. However, there is a cheaper, natural way to do this at home. Here is an easy way to get yourself some long, thick, beautiful eyelashes with simple, natural products. What You Will Need: 100% pure castor oil 100% EV olive oil and vaseline