If you have someone in your organisation who already knows how to use DoubleTake for non-database files, then ask them about setup and configuration. There may be some site standards you should follow.

You can then do some research to find out about the differences that relate to database files with DoubleTake.

Finally, I strongly recommend you start using DoubleTake with a sandbox test environment where you can try various configurations and see what works and what breaks SQL Server. You need to try various fail-over scenarios so you gain confidence in using the product.

If you do all the above, it is likely you will need about 3 months between the time you start learning about DoubleTake to the time it is safe to put this on to a production DB server. If you need to get into production sooner then the best option is to get some expert consultancy help on-site to show you what to do.

At my old place they used DoubleTake to replicate SQL DBs between two GB data centres, using an active/passive failover concept. This worked well for a number of years until a major infrastructure upgrade that moved to GB and US data centres with SAN replication.