diff --git a/Dockerfile b/Dockerfile
index 82335b3..375030c 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,4 +2,4 @@ FROM openresty/openresty:1.27.1.2-0-bookworm-buildpack
 
 RUN luarocks install sitegen
 
-CMD ["openresty", "-p", "/opt", "-g", "daemon off;"]
+CMD ["openresty", "-p", "/opt/", "-g", "daemon off;"]
diff --git a/README.md b/README.md
index bf3d50c..b8baa3c 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,52 @@
-## run default openresty
+## start default openresty
 
 1. Run `docker run --rm -it --init -w /opt -v $PWD:/opt -p 80:80 openresty/openresty:1.27.1.2-0-bookworm-buildpack`
 2. Visit `localhost` in web browser.
+
+## start a custom site
+
+### build docker image
+
+    $ docker build -t sitegen-openresty .
+
+### generate a new site file
+
+    $ docker run --rm -w /opt -v $PWD:/opt sitegen-openresty sitegen new
+
+### add an index page
+
+    $ docker run --rm -w /opt -v $PWD:/opt sitegen-openresty sitegen page /opt/ index
+
+### add to `site.moon`
+
+    add "index.md"
+
+### add config for nginx
+
+    $ mkdir logs/ conf/
+
+    # conf/nginx.conf
+    worker_processes  1;
+    error_log logs/error.log;
+    events {
+        worker_connections 1024;
+    }
+    http {
+        server {
+            root /opt/www;
+            listen 8080;
+            location / {
+                default_type text/html;
+            }
+        }
+    }
+
+### build site
+
+    $ docker run --rm -w /opt -v $PWD:/opt sitegen-openresty sitegen
+
+### start server container
+
+    $ docker run --rm -it --init -w /opt -v $PWD:/opt -p 8080:8080 sitegen-openresty
+
+### visit `localhost:8080` in web browser