No need to wait in line for Microsoft to deliver Windows 10 via Windows Update to you --- you can install it right now, and it's a breeze to do.
If you didn't sign up for the Windows Insider testing program, you would normally have to wait in line to install Windows 10. But Microsoft has quietly released a download that lets you update to Windows 10 right away. You can also create an ISO file and upgrade that way, and use it on multiple PCs.
First, make sure you've backed up your data and anything else you want to keep, just in case the installation goes wrong. Next, make sure that your machine is eligible for the free upgrade. You need a machine with Windows 7 SP1 or Windows 8.1, with a valid registration. Pirates need not apply.
You also must have a machine that meets these minimum system requirements:
- OS: Windows 7 SP1 or Windows 8.1 Update
- Processor: 1GHz or faster
- RAM: 1GB RAM for a 32-bit system or 2GB RAM for a 64-bit system
- Hard drive space: 16GB for a 32-bit system or 20GB for a 64-bit system
- Graphics card: DirectX 9 or later with WDDM 1.0 driver
- Display: 1024 x 600 resolution
Once you do all that, you're ready to upgrade. Head to Microsoft's Download Windows 10 page and then click either "Download Tool Now (32-bit version)" or "Download Tool Now (64-bit version)" depending on your machine. Then run the file that downloads to your PC. When you do that, you'll have a choice of either upgrading your PC right then, or else creating an ISO that you can use to upgrade multiple PCs.
When you choose "Upgrade this PC Now," you'll download in the background the files you need to upgrade to Windows 10. Be prepare to wait. It took about two hours for mine to download. You can keep working during the download.
After the download, you'll be prompted to install Windows 10. You may be a bit confused at some point, because you'll see the message "Creating Windows 10 media." That sounds as if it's creating an ISO file you'll then have to use on your own to install Windows 10. But that's not what it's doing. In a bit, that message disappears and you'll be prompted to install Windows 10. Follow the prompts. After installation, if for some reason you want to revert back to Windows 7 or Windows 8.1, head to Settings --> Update & Security --> Recovery and then choose to go back to the version of Windows from which you upgraded.