Cannot initiate Windows 7 install on MacBook Air bootcamp I use the latest Yosemite version on MacBook Air, I am trying to install Windows 7...

I start bootcamp, I select the first two checkboxes

[X] create windows 7 install disk

[X] download support software

[  ] remove windows 7 or later version

The windows partition already exists from previous similar attempts.

Asks me for path to Windows 7 ISO and the USB stick to use.
After I wait a few hours to setup the stick, it tells me that it installed the support software and that I should use this software after I install windows.
The only button now is [QUIT]. I press quit and it exists, it never starts the windows 7 install as I expect.

If I reboot and hold option button pressed, the "windows" stick doesn't start, it complains about missing bootable disk or something similar.
What am I doing wrong ? This newly created Win7 USB stick works to boot on other PCs, I tried it.
I got it sorted, it was probably my fault not understanding the options properly.
The actual install can only be started by that last option that says eider:

remove windows 7 or later version

OR

install windows 7 or later version

So if you already have a Windows partition created you will see remove windows 7 or later version, you need to remove it and then it will change into install windows 7 or later version, after creating the partition again, it will restart and the install will begin.

If you already have the bootable stick previously created by these steps, just plug it without checking first two boxes (create boot stick, download support software), creating that stick would take hours.

I think Apple could make it more clear (the re-install part).