Q: Constant Wifi connectivity issues since updating Yosemite

In the last few weeks I allowed an update that had been trying to download and re-boot my MacBook air. Since then my Wifi constantly disconnects and I have to turn it off and on again to get it to work. It will then work anywhere from a few minutes to about 10 minutes before it stops working again.

I have searched the net for a solution and tried the following off this link http://osxdaily.com/2014/10/25/fix-wi-fi-problems-os-x-yosemite/

1. Remove Network Configuration & Preference Files
2. Create a New Wi-Fi Network Location with Custom DNS
3. Reset SMC
4. Unload & Reload discoveryd to Fix DNS & Wi-Fi Failures in OS X Yosemite

None of it has worked. I am quite capable of following instructions although I'm not sure what the majority of the solutions mean.

Does anyone have any idea of what I could do? I really don't want to do a reinstall for obvious reasons but am considering downgrading from Yosemite.

This is really making my Mac unusable, any help gratefully received.