I'm not doing web develoment myself, but I assume that the approach for web development is exactly the same as for other big developments (which my team IS doing). In that case, the following tips might help:
- Use version management (SVN, ...)
- Be agile (this is also resembled by the following points)
- Make a mixed team (developers, testers, designer, functional responsibles, ...) that all work as an integrated team on the same subject. Make sure the whole team communicates.
- Make everyone responsible for the whole project. Never blame individuals if things go wrong.
- Be sure the whole team knows the status of the project: where are we, what should still be done, ... Make everything visual by sticking graphs and sheets to your office wall.
- Keep the time between 'raised questions or raised problems' and the answer or solution short. E.g. if a bug is found, log it immediately and try to solve it as soon as possible.
- Develop incrementally. Don't develop for several months and then start testing, but make sure you have a working copy every day.
- Split development/design/... tasks in smaller tasks that can be developed incrementally (see previous point) and in a minimal amount of time (a day or a few days).
- Automate tests as much as possible.
- Use continuous integration (where the tests are run at every commit in the version management system)
- As a manager, support your team.
- Focus
- Shield the people of the team from all kind of problems not directly related to the project (e.g. PC problems, printer problems, ...). Choose a 'scrum manager' that solves all these annoying problems for the team.
- Demonstrate the results at regular intervals to your customer, your boss, ...
- Give a reception if an important milestone is reached.
There are probably many more tips. Therefore, read a good book about managing software development. There is probably no essential difference between web development and other software develoments.