add section

added section on how to use this program

README.md

@@ -1,3 +1,19 @@
 # sort_c
 
-I am learning C by implementing as many sorting algorithms as I want
+I am learning C by implementing as many sorting algorithms as I want
+
+## How to use
+
+First you have to clone this repository
+```bash
+git clone https://gitea.hopeless-cloud.xyz/AustrianToast/sort_c.git && cd sort_c
+```
+Now you should be inside the downloaded repository.<br>
+To compile this you can execute
+```bash
+gcc -o main main.c
+```
+Now you can run it like this
+```bash
+./main
+```