docs: how to use section

Author: maximivanov

CONTRIBUTING.md

@@ -1,17 +1,5 @@
 # Contributing
 
-## Branch Naming
-
-```text
-type/humanFriendlyDescription
-```
-
-Example:
-
-```text
-chore/upgradeLodashToLatestVersion
-```
-
 ## Commit Format
 
 Commit message is validated with

README.md

@@ -2,7 +2,7 @@
 
 Use this worker to password-protect whole websites or some areas/specific pages.
 
-E.g. limit access to a staging version of a static website you're building.
+_E.g. limit access to a staging version of a website you're building._
 
 ## Demo
 
@@ -15,6 +15,78 @@ User name: `demouser`
 
 Password: `demopassword`
 
+## How to use
+
+Requirements:
+
+- your website's DNS is managed by Cloudflare
+- corresponding DNS record is proxied (orange cloud)
+
+In order to protect your website with this worker you will
+need to deploy worker code and configure route mapping.
+There are multiple ways you can deploy workers, here are couple options for your
+consideration.
+
+### Option #1. Deploy manually via CF dashboard
+
+If you care about _Infrastructure as Code_, skip to Option #2.
+
+Create a worker.
+
+- Go to Cloudflare Dashboard / Account Home / `Workers`
+- `Create a Worker`
+- Paste the code
+- `Save and Deploy`
+
+Configure route mapping.
+
+- Go to Account Home / Domain / `Workers`
+- `Add route`
+- Provide route, e.g. example.com/protected/\*
+- Select worker
+- `Save`
+
+You're set! If you open `example.com/protected/anything` now it will prompt you
+to enter password.
+
+### Option #2. Deploy with Wrangler
+
+Wrangler is a tool built by Cloudflare to develop, test and deploy workers code.
+For more thorough overview, check
+[documentation](https://developers.cloudflare.com/workers/quickstart).
+
+First you need to collect some information from your CF account.
+
+- Account ID.
+  - Account Home / Domain / `Overview` tab / `API` section / `Account ID`
+- Zone ID.
+  - Account Home / Domain / `Overview` tab / `API` section / `Zone ID`
+- API token.
+  - Account Home / Domain / `Overview` tab / `API` section / `Get API Token`
+  - `Create Token`
+  - `Start with Template`
+  - Select the `Edit Cloudflare Workers` template
+  - `Continue to Summary`
+  - `Create Token`
+
+Install Wrangler. `npm install -g @cloudflare/wrangler`
+
+Create Wrangler config. `wrangler init --type javascript`
+
+Update Wrangler config. Example:
+
+```
+name = "cf-worker-basic-http-auth"
+type = "javascript"
+account_id = "<YOUR ACCOUNT ID>"
+zone_id = "<YOUR ZONE ID>"
+route = "example.com/protected/*"
+```
+
+Configure API token. `wrangler config`
+
+Deploy worker. `wrangler publish`
+
 ## Contributing
 
 see [CONTRIBUTING.md](CONTRIBUTING.md)