You can start out easy with a few bottles of Lorran flavors and experiment with some base juices made by vendors. Jazz them up with a drop of Lorran flavor and learn how much to add to a bland juice to make it what your want. You can also buy plain PG and/or VG juices with nicotine but no flavorings for that reason. That way, for a little extra you don't have to handle 100mg nicotine yourself.
I like Dekang Tobacco with Lorran Key Lime and a little Lorran Cotton Candy added. I also like the same Dekang Tobacco liquid with English Toffee or Butter Rum Lorran flavor added. They can be better than what you order from some vendors if you find the exact mix that satisfies your taste buds.