In TeX literal double quotes `"like this"' is seldom used, instead two single quotes is used `"like this"'. To help you insert these efficiently, AUC TeX allows you to continue to press " to insert two single quotes. To get a literal double quote, press " twice.
Command: TeX-insert-quote count
(") Insert `"', `"' or `"' according to preceding character. With prefix argument, insert count `"' characters.
Users of `german.sty', or other people who uses the literal `"' often, will want to disable this feature. They can do that by inserting the following hook in their `.emacs' file.
(setq TeX-mode-hook
(function (lambda () (local-set-key "\"" 'self-insert-command))))
The style hook file for `german.sty' will do this automatically, so if you use `german' as a style option for `\documentstyle' " will insert a literal `"', but only after the style hooks have been applied. You can force the style hooks to be applied by pressing C-c C-n.
To avoid unbalanced braces, it is useful to insert them pairwise. You can do this by typing C-c {.
Command: TeX-insert-braces
(C-c {) Make a pair of braces and position the cursor to type inside of them.