I have a repetitive task:

1. Download SQL Server Express edition from my own site or MS Site
2. Install SQL Server (mixed auth mode, specific collation etc etc)
3. Attach a database (compressed into a file) to my new installation
4. Create some users
5. Create file connection string according to my new installation

I know just one or two PowerShell commands but think is possible to accomplish this with it.

My question is how can I do that?