The easiest way is going to http://www.ernestdelgado.com/drupal
Use any of the following users: test1 (login: test1, password: test1), test2 (login: test2, password: test2) or test3
Create any type of content (story, page). Once the content is created go to the edit section to do collaborative edition
Notes:
If you experiment weird behaviour at the beginning press F5 and start again.
Different things you can test:
To test different use cases write, replace, delete, copy, paste any type of content at any position. Check if other users get your modifications after few seconds
If you want to know about the different use cases would be good to read Use cases beforehand.
Replace or delete content and quickly write something in that place with the other user. A collision alert should be shown and the last change should be undone
To understand better the collision cases read Collision detection
Use one user (i.e. test1) and place the caret anywhere in the text or even select a word or a chunk of text. With the other user (i.e. test2) write something anywhere. To do harder tests write something before or next to the selection of the first user. See how the new content of the second user is shown up into the first user textarea. Check the caret is between the same letters as before or the selection is highlighting the same words.
To know more about how to preserve the caret position read Caret position
Write content with one user and quickly go to the other user and write content without pause. Check the content from the first user is only updated when you stop writing with the second user
To know more about this subject read Stop typing
Play with new scenarios and use the debug variables to follow better what is happening
Try to improve the workflow of any of the points above and write any line to get better performance. Also change any pointless variable or statement you could notice
Paste urls or snippets that could do the same in few lines or purpose alternatives even from a more theoretical point of view. There are more related articles in the project group
If you want to install the module in your server (for testing purposes) follow the instructions of the INSTALL.txt file in the cvs repository