Cleaned up contributing.md wording

contributing.md

@@ -1,17 +1,17 @@
 # Send your tip!
 
-The purpose of esta handbook is the last language use features without losing performance.
+The purpose of this handbook is to learn how to use JS language features without losing performance.
 
-You can see on [Six Speed](https://kpdecker.github.io/six-speed/) how faster ES6 run. Also use [Node Green](http://node.green/) to know the native support of each feature.
+You can check [Six Speed](https://kpdecker.github.io/six-speed/) to see how much faster ES6 runs. Also, [Node Green](http://node.green/) displays the native support of each feature.
 
 If you want to submit a tip, create a PR in our [GitHub repository](https://github.com/Kikobeats/js-mythbusters).
 
 Before adding your tip, take into consideration the following guidelines:
 
-- Add your tip in the correct section. Each different section is a folder (for example [v8-tips](https://github.com/Kikobeats/js-mythbusters/tree/master/v8-tips) or [workflow](https://github.com/Kikobeats/js-mythbusters/tree/master/workflow)).
+- Add your tip in the correct section. Each folder is a different section (for example [v8-tips](https://github.com/Kikobeats/js-mythbusters/tree/master/v8-tips) or [workflow](https://github.com/Kikobeats/js-mythbusters/tree/master/workflow)).
 - Inside the folder, each file is a tip.
 - If your tip is very similar to a tip that already exists, consider extending the first tip.
 - Don't add more than one tip per file.
-- The text that describes the tip has to be concise and precise.
-- To avoid extending tips till they are too big, you can reference other tips instead.
+- The text that describes the tip should be concise and precise.
+- Avoid bloated tips - you can reference other tips instead.
 - Add the correct [resources](https://github.com/Kikobeats/js-mythbusters/blob/master/resources.md) associated with the tip.