diff --git a/README.md b/README.md
index 7ff852b..38d5d6e 100644
--- a/README.md
+++ b/README.md
@@ -58,7 +58,7 @@ You can increase the `frag_duration` (microseconds) to slightly reduce the file
 ## TLS
 Unfortunately, QUIC mandates TLS and makes local development difficult.
 
-If you have a valid certificate you can use it instead of self-signing. The go binaries take a `-cert` and `-key` argument. Skip the remaining steps in this section.
+If you have a valid certificate you can use it instead of self-signing. The go binaries take a `-tls-cert` and `-tls-key` argument. Skip the remaining steps in this section and use your hostname instead.
 
 Otherwise, use [mkcert](https://github.com/FiloSottile/mkcert) to install a self-signed CA:
 ```
@@ -78,7 +78,7 @@ go run main.go
 This can be accessed via WebTransport on `https://localhost:4443` by default.
 
 ## Web Player
-The web assets need to be hosted with a HTTPS server. If you're using a self-signed certificate, you will need to ignore the security warning in Chrome (Advanced -> proceed to localhost). This can be avoided by adding your certificate to the root CA but I'm too lazy to do that.
+The web assets need to be hosted with a HTTPS server. If you're using a self-signed certificate, you may need to ignore the security warning in Chrome (Advanced -> proceed to localhost).
 
 ```
 cd player
@@ -88,6 +88,8 @@ yarn serve
 
 These can be accessed on `https://localhost:4444` by default.
 
+If you use a custom domain for the Warp server, make sure to override the server URL with the `url` query string parameter, e.g. `https://localhost:4444/?url=https://warp.demo`.
+
 ## Chrome
 Now we need to make Chrome accept these certificates, which normally would involve trusting a root CA but this was not working with WebTransport when I last tried.