If you don't know the URL of the site, open the IIS manager, select your installed EPiServer site and select browse in the context menu of the site node. Now the site should open. After that you should be able to login to the site and after you have logged in you can right click on the page to get a context menu with optiions to take you into for instance the editorial view.

Thanks. I did all as you told me before but when I try to open the site on IIS7 a message appears: 

Have you installed the Alloy demo templates via Deploymentcenter?

No, but I installed a new site including Alloy site.

Now I can see the site, and the question is how can I edit pages for this site?

In upper right you have a "Log in" link. The alloy site is by default configured to use windows member and role provider so you should be able to login with a local windows admin account.

After successful login you can right click and get the EPiServer context menu and choose "Edit."

I wrote something like "Domain\user" and my password but it didn't work

I wrote something like "Domain\user" and my password but it didn't work

Try skipping the domain part and just use username/password.

It didn't work again.

Just create a local account on your machine and try logging in with that. You might not be able to login if you are using a domain account and you are currently not connected to the domain (might be the case for a laptop that you are using when not connected to the domain). The easiest way to get access to everything with this account is to make him part of the administrators group on the machine.

Excellent, thanks. I can edit content.