Download a couple of APKs, you can usually find the newest bundle in a zip package:
*Google Play Store (the newest version you can find)
*Google Services Framework
*Google Login Service/Account Manager
If you are rooted you can copy them to your root directory to System/App using a root manager like ES File Explorer. Then just restart your device.
If this doesn't work first time you might need to change the permissions on the new APKs to match the rest on your device. Use a file explorer like ES for this. Apparently if you're not rooted you can simply install each APK then reboot and it works for some devices. This sounds a little fishy to me but you never know.
Reboot and add your Google account in Settings > Accounts > Add account.
Look for the Play Store in your app drawer....