add example usage

Author: Puneeth-n

README.md

@@ -1,2 +1,34 @@
-# terraform-aws-firehose
-Terraform AWS Kinesis Firehose module
+# Terraform AWS module for AWS Kinesis Firehose
+
+## Introduction
+
+This module create a Kinesis Firehose and all the resources related to it to log to S3.
+
+## Usage
+
+```hcl
+module "my_firehose" {
+  source = "github.com/comtravo/terraform-aws-firehose"
+
+  enable = 1
+
+  name        = "test-firehose"
+  destination = "s3"
+
+  s3_configuration {
+    bucket_arn      = "my_s3_bucket_arn"
+    buffer_interval = 60
+    prefix          = "some-prefix/"
+  }
+
+  account_id = "0123456789012"
+}
+```
+
+## Authors
+
+Module managed by [Comtravo](https://github.com/comtravo).
+
+## License
+
+MIT Licensed. See LICENSE for full details.