diff --git a/.gitignore b/.gitignore
index ed67414da7..48f0b97f90 100644
--- a/.gitignore
+++ b/.gitignore
@@ -20,3 +20,10 @@ hasura.planx.uk/.env.test
 /playwright-report/
 /playwright/.cache/
 api.planx.uk/tmp/
+
+# Ignore certificate files
+*.chain
+*.key
+*.pfx
+*.pkcs12
+*.p12
\ No newline at end of file
diff --git a/doc/how-to/how-to-setup-custom-subdomains.md b/doc/how-to/how-to-setup-custom-subdomains.md
index 52e50c18b4..c75b3b2782 100644
--- a/doc/how-to/how-to-setup-custom-subdomains.md
+++ b/doc/how-to/how-to-setup-custom-subdomains.md
@@ -33,8 +33,8 @@ This guide will walk through the process of setting a custom domain for a new te
 
 4. **PlanX** - Format certificates if provided with PKCS #12
     ```shell
-    openssl pkcs12 -nocerts -nodes -in <FILENAME> -out council.key [ -password pass:<PASSWORD> ]
-    openssl pkcs12 -nokeys -in <FILENAME> -out council.cert [ -password pass:<PASSWORD> ]
+    openssl pkcs12 -nocerts -nodes -in <FILENAME> -out council.key [ -password 'pass:<PASSWORD>' ]
+    openssl pkcs12 -nokeys -in <FILENAME> -out council.cert [ -password 'pass:<PASSWORD>' ]
     ```
     
     The `.cert` file might contain the certificate chain inside it, so please separate the first certificate in the file (the certificate body) from the rest of the certificates in the file (the certificate chain).