Q: Sites directory not working

I updated to El Capitan yesterday. I cannot get my machine back to were it was before the update. I use the LAMP stack. I got Apache to work and can get the "It Works!" page, fine. Then I try my work under /user/my username/Sites" and I get the error "The requested URL /~my username/test.php was not found on this server." This worked before the upgrade.

I spent the entire day following pages on the web describing how to fix this. I still get the error "The requested URL /~my username/test.php was not found on this server." Will php work after I get over this hurdle? I know MySQL is not working either. I an very disappointed, if this is what an OS upgrade costs, this might be the last OS upgrade I do.

Can anyone supply accurate succinct instructions to get the LAMP stack running again after upgrading to El Capitan.

Thanks!