As a hair extension specialist, I'd say that 70% - 80% of hair extension request I get are for Microlink and Sew-in. They are both very popular methods right now. Microlinks and Sew-In Hair Extensions are great for medium to thick hair.
Microlinks are especially popular because clients are able to pull their hair into a high ponytail easily.
Sew-In Hair Extensions have always had a certain level of popularity. They have been around for ages. The newer Sew-In Hair Extension method have removed braiding all together. Now, hairstylists can install Sew-In Hair Extensions without the hassle of braiding and the excess tension that braiding causes. Microlink and Sew-In Hair Extension Workshop are courses available for you to learn and get certified in the most popular method.
To sign up for Hair Extension Training visit:
Certified Hair Extension Educator