First of all, you probably shouldn't indent the first paragraph. Look in nearly any professional publication and you'll find that the first paragraph is never indented. It's a standard typographical rule.
If you still want those paragraphs indented, the best way to do this is to use the indentfirst style option. You will need to copy a file from the consult locker to the directory where your LaTeX files are. Assuming that you keep your file in the directory ~/latex, you would type:
If your files are in another directory, then use the name of that directory rather than ~/latex.
Then, in any latex file you want to change, add the line
after your \documentclass line.
|Sharing your document|
Please note that the indentfirst package is specific to MIT and is not part of standard LaTeX distributions. If you are sharing your LaTeX source files with anyone, you will need to include the indentfirst.sty file as well.