Be precise and exhaustive in your commit comments, try to have a standard for your company.
Commit your work to the repository as often as you can without breaking the build. Always check-in a compiled version of code in order not to prevent others from continuing work if updated their working folders. Don't let your working folder become too valuable.
Keep in touch with the repository i.e. update your working folder as often as you can without interrupting your own work. It isn't wise to let the distance between your working folder and the repository grow too large.
If you used merge, merge manually & make sure you have a compiling version before commit.