Update README.md

README.md

@@ -6,3 +6,13 @@ Provides a datastructure for storing triangles based on how far they are from a
 The datastructure is capable of performing the following queries:
   1. for a point, get the closest triangle
   2. get the visible surface area
+
+## Building
+```
+mkdir build
+cd build
+cmake ..
+make
+./tests
+```
+