Changing My Site User Storage Free Space

Problem
Some users where recieving a message from the SharePoint server about there My Site:

You are receiving this e-mail message because you are an administrator of the
following SharePoint Web site, which has exceeded the warning level for storage: http://yoursite.domain.com/. To see how muchstorage is being taken up by this site, go to the View site collectionusage summary: http://yoursite.domain.com/_layouts/Usage.aspx.

If you would browse to the _layouts/usage.aspx page, you will find information about the space the user is allocating. My My Site however is just created, so you won't find a mess in there (yet ;-)

But how do we change the Storage Space of a My Site when the free space is empty?

Tempory solution
The owner of the My Site can browse to the ‘storage space allocation page’ and clean up some mess, like empting the recycle bin or removing old/unnessasery files.

Solution
Every My Site is created in it's own site collection. This way it's possible to change the storage available for your site.

Browse to the Central Administration (CA) and select the 'Application Management'-tab and browse to 'Site collection Quotas and locks'.

Or go to http://[CA-url]/_admin/sitequota.aspx

First choose the right site collection by clicking on the url in the right upper corner and then clicking 'Change Site Collection'.

Next you need to change the selected web application into the web application that is hosting the My Sites. Last you need to select the site collection of the right My Site and click OK.

Note: In the top of the page there is telling you
there are more then 10 site collections. You can use the arrow
to browse through all site collections.

Change the 'Site Quota Information' by changing the 'Current quota template' to Individual Quata and change the maximal storage space to 250 mb, for example.