Update CONTRIBUTING.md

Author: SergeStinckwich

CONTRIBUTING.md

@@ -2,17 +2,23 @@
 
 This file is currently not complete but will be improve step by step.
 
-
 # Contributing code
 ## Fork the Pharo repository
 
 All changes you'll do will be versionned in your own fork of the [https://github.com/PolyMathOrg/PolyMath](PolyMath repository). Then, from your fork you'll be able to issue pull requests to PolyMath, where they will be reviewed, and luckily, integrated.
 
 Go to PolyMath github's repository and click on the fork button on the top right. Yes, this means that you'll need a github account to contribute to PolyMath, yes.
 
+## Load last dev version of PolyMath
+In a fresh Pharo, load last development version of Polymath : 
+
+```Smalltalk
+```
+
 ## Setup Iceberg
+Open Iceberg tool
 
-## Cleanup
+## Cleanups
 Ounce your pull request is integrated, some cleanups are required:
 - remove your branch from your fork
 - close the issue (tips: you can automatically close the issue n, by inserting the sentence: **close #n** when you merge your pull request).