Texture baking allows you to get the basic coloration for your model straight from the reference image into your uv map with in a few minutes. The quality of your baked texture depends on the quality of your reference image. With the color map, you can add more details to your texture by hand. This methods give you a starting point for your texturing work, because a blank canvas can be an artist’s arch enemy.
Download the package of assets for this tutorial here: https://www.dropbox.com/s/se789hvdsuz5ybf/Tut-package.zip?dl=0
For a more in-depth instruction, check out my blog: https://billnguyencg.wordpress.com/2016/12/20/texture-baking-tutorial-a-gift/