readme: Add in a note about how to install and use from pip

Change-Id: Ie4986fff449dfc6eb8471c1ae30eed16e70d200e
diff --git a/README.md b/README.md
index f5fe028..91389bc 100644
--- a/README.md
+++ b/README.md
@@ -15,3 +15,15 @@
 With minimal effort, MDT should also be portable to existing systems such as
 Debian and Ubuntu, if needed. This, however, is out of the scope of this
 project.
+
+## How do I use it?
+
+Install it via pip like this:
+
+```
+pip install mendel-development-tool
+```
+
+Note that if you run this as a non-root user, the executable will be stored in
+`$HOME/.local/bin` which may not be in your PATH environment variable, so you'll
+want to add it.