How do you build your own house in skyrim?

In The Elder Scrolls v skyrim, in order to purchase a house, you will need to download the elder scrolls v hearthfire which then allows you the option to purchase three plots of land. Falkreath, Dawnstar, and maybe Morthal. Each costs 5000 coin and comes with an anvil, a chest filled with supplies, and a workbench. Trolls and bandits will attempt to enter your house. You may only build 3 wings on your house, a cellar, and a few balconies. You will need clay which can be mined near your manor, after you do a bit of searching, quarries stone which is displayed behind the battle born farm next to the city of Whiterun, and sawn logs, which can be purchased at the half moon mill which is a complete frost dragon magnet, so be careful. As well as iron, which can be bought from blacksmiths at major city's.

I've had skyrim for a few years.