This simple workflow will make sure you always work with the most up to date version and will not cause any head conflicts when pushing your work into your repository.
Before you start coding runs these two commands
1. Get the current version from the repo
2. Make sure all files in your branch are updated
3. Make as many commits as possible over the course of your working day (or session).
hg com -m "You commit message"
4. At the end of the day (or session) start with the same two comannds at the beginning.
You get the current version from the repo and by using update you make sure all changes made by others in your team are now part of you code.
There may be conflicts with the files you worked on today. If that is the case each conflict should be resolved and another commit like in step 3 is neccessary.
5. Finally push your commits to the repository.