Expand readme

Author: tygern

.gitignore

@@ -1 +1,2 @@
 build/
+pi

README.md

@@ -1,10 +1,42 @@
 # Pi Estimation
 
-Estimates the value of π using a Monte Carlo simulation.
+Estimates the value of π using the [Monte Carlo method](https://en.wikipedia.org/wiki/Monte_Carlo_method).
 
 ## Method
 
 We generate random points within the unit square and count how many fall within a circle of radius 1 centered at the origin.
 The ratio of the number of points within the circle to the total number of points approaches π/4.
 
 ![Illustration of a Monte Carlo simulation](./readme_images/monte-carlo.svg)
+
+## Run Estimation
+
+Build and run an estimation with the default configuration.
+
+```shell
+go build ./cmd/pi
+./pi
+```
+
+Use the `--help` flag to see configuration options.
+
+```shell
+./pi --help
+```
+
+## Development
+
+1.  Run tests
+    ```shell
+    go test ./...
+    ```
+
+1.  Check formatting
+    ```shell
+    gofmt -d .
+    ```
+
+1.  Check linking
+    ```shell
+    go vet ./...
+    ```