You can use this tutorial PDF files which has commands that can be used on MHF. It was created by MathMan.
Also, this forum has a latex mini-forum where users can test latex. It has many tested latex by users which can be useful and has some useful external links too.
Another point, google is your friend, so a search on google will bring many Latex help. Within a few days/weeks, you too will be a latex expert.