Update readme

README.md

@@ -6,6 +6,57 @@
 
 **Work in progress! First estimated preview: end of April**
 
+## Installation
+
+Download the [latest](https://github.com/twirphp/protoc-gen-twirp_php/releases/latest) release from the Releases page
+and put it into your `$PATH` prefix (or any location, but that requires some configuration, see later).
+
+This is a [protoc](https://github.com/golang/protobuf), so you will have to install that as well.
+
+Alternatively you can manually download and build the project. For that, you are going to need [dep](https://golang.github.io/dep/).
+
+```bash
+$ go get github.com/twirphp/protoc-gen-twirp_php
+$ cd $GOROOT/src/github.com/twirphp/protoc-gen-twirp_php
+$ dep ensure
+$ go install
+```
+
+
+## Usage
+
+Use it like any protoc plugin to generate both server and client code:
+
+```bash
+$ protoc -I example/ --php_out . --twirp_php . service.proto
+```
+
+If you downloaded the generator outside of your `$PATH` prefix, you need to manually pass the location to the compiler:
+
+```bash
+$ protoc -I example/ --plugin=protoc-gen-twirp_php=path/to/protoc-gen-twirp_php --php_out . --twirp_php . service.proto
+```
+
+
+### Server
+
+In order to use the server you have to install some dependencies to your PHP project via [Composer](https://getcomposer.org/):
+
+```bash
+$ composer require twirp/twirp
+```
+
+You need to choose a [PSR-7](http://www.php-fig.org/psr/psr-7/) implementation along with it's [factory](https://github.com/php-http/message-factory):
+
+```bash
+$ composer require guzzlehttp/psr7 php-http/message
+```
+
+The code generator creates a service interface which you need to implement.
+
+TODO: create and example an link it here
+
+
 ## License
 
 The MIT License (MIT). Please see [License File](LICENSE) for more information.