Update README.md

Author: dim-s

README.md

@@ -3,3 +3,33 @@
 [![Build Status](https://travis-ci.org/jphp-group/tester.svg?branch=master)](https://travis-ci.org/jphp-group/tester)
 
 Unit Testing Framework for JPPM
+
+# How to use?
+
+1. Add `tester` dependency to `devDeps`.
+
+```
+jppm add tester -dev
+```
+
+2. Create `tests` directory in root of your package dir.
+3. Create your first test class, e.g:
+
+```php
+use tester\{TestCase, Assert};
+
+class SimpleTest extends TestCase 
+{
+  function testFeature()
+  {
+    $actual = "expected";
+    
+    Assert::isEqual("expected", $actual);
+  }
+}
+```
+
+4. Run your tests.
+```bash
+jppm test
+```