To get started, you'll need the Serverless Framework installed. You'll also need your environment configured with AWS credentials.

Then, let's install a few dependencies. We'll install the express framework, as well as the serverless-http:

$ npm install --save express serverless-http
Then create a file index.js and initialize it like so:
const serverless = require('serverless-http');
const express = require('express')
const app = express()

app.get('/', function (req, res) {
res.send('Hello World!')
})

module.exports.handler = serverless(app);

The serverless-http package is a handy piece of middleware that handles the interface between your Node.js application and the specifics of API Gateway.

Then create a file serverless.yml:

service: my-express-application

provider:
name: aws
runtime: nodejs6.10
stage: dev
region: us-east-1

functions:
app:
handler: index.handler
events:
- http: ANY /
- http: 'ANY {proxy+}'

Now deploy

$ sls deploy 

Hooray! congratulations

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