adds the manual installation

docs/pages/installation.md

@@ -7,6 +7,8 @@ weight: 30
 
 Before installing Glee into your project, make sure you have pre-installed NPM, NodeJs and [AsyncAPI CLI](https://github.com/asyncapi/cli) tools on your system.
 
+### Automatic Installation
+
 The best way to get started with Glee is by using AsyncAPI CLI, which sets up everything automatically for you. 
 To create a project, run:
 
@@ -31,3 +33,87 @@ Also, you can already open the project in your favorite editor and start tweakin
 ```
 
 While making twists to your application, you can follow along with our getting started guide on the relevant page.
+
+### Manual Installation
+
+To manually create a new app, create a folder e.g. `myapp` and install the required packages:
+
+```js
+npm init -y
+npm install @asyncapi/glee
+```
+
+Open your package.json file and add the following scripts:
+
+```js
+{
+  "scripts": {
+    "docs": "glee docs",
+    "dev": "glee dev",
+    "start": "glee start",
+  }
+}
+```
+
+These scripts refer to the different stages of developing an application.
+
+- `glee docs`: This script generates documentation for your project using the "Glee" documentation tool. This documentation includes information about your project's APIs, modules, and usage instructions.
+
+- `glee dev`: This script is used for starting a development server. It launches a local development server, build your project in development mode, or perform other development-related tasks.
+
+- `glee start`: This script is responsible for starting your project or application. It is used to launch a production-ready server or application instance.
+
+#### Creating `asyncapi.yaml` file and other required directories
+
+Create a yaml file that supports capable of receiving a "hello {name}" message with the protocol as `ws` and the channel name  as `hello` the hello API will subscribe to. The operationId property is `onHello` that's the name of function and the payload property is type string publishing to that channel.
+
+```yaml
+asyncapi: 2.6.0
+info:
+  title: Hello, Glee!
+  version: 0.1.0
+
+servers:
+  websockets:
+    url: ws://0.0.0.0:3000
+    protocol: ws
+
+channels:
+  hello:
+    publish:
+      operationId: onHello
+      message:
+        $ref: '#/components/messages/hello'
+    subscribe:
+      message:
+        $ref: '#/components/messages/hello'
+
+components:
+  messages:
+    hello:
+      payload:
+        type: string
+```
+
+Create an operation function `onHello.js` inside `myapp/functions`:
+
+```js
+export default async function (event) {  
+  return {
+    reply: [{
+      payload: `Hello from Glee! You said: "${event.payload}".`
+    }]
+  }
+}
+
+```
+Finally, create a `.env` file specifying a server name:
+
+```
+GLEE_SERVER_NAMES=websockets
+```
+
+#### Run the Development Server
+
+- Run `npm run dev` to start the development server.
+- Connect to `ws://localhost:3000/hello` and send a WebSocket request with a payload e.g. {"john"}