So yeah, I have decided to take the plunge and invest some cash into converting an old Colnago road bike frame into a fixed gear ride. The problem is, I have no idea what to do. I have the frame stripped and ready to use, can I just buy a fixed-wheel for the rear and buy a chain, hook it all up and go? I am thinking it would be wise to find a flip/flop hub so that I can switch to SS if I need to, but someone told me that with a flip/flop hub I would need to buy a lockring as well. Is there a detailed how-to guide someone can recommend to me? Or is there an archived thread that entails all that I need to know? Thanks for any and all help.

https://sheldonbrown.com/fixed-conversion.html

You will not find better, more practical, or safer advice on this topic on the internet. And yes, if it is your first fixed-gear bike it is recommended you use a flipflop hub. Otherwise, welcome!!

I agree with Slodo, sheldon brown is the most thorough resource around. A flip-flop is a great idea, too. You'll find you've got muscles you didn't know you had riding a fixie. Being able to freewheel at times is a refreshing thing. It's like having two bikes at once. Here's another link with tons of owner photos and a help section, too. Best of luck. I hope you enjoy fixed riding! jot

https://www.fixedgeargallery.com/

Personally I wouldn't bother with a flip flop just because I don't know one person that has one that actually flips thier flop. That and if you're going to be keeping the option of a freewheel you're probally going to want to keep the rear brake. And you know what they say, "once you go fixed....you'll...stop picking up sticks?" Or something like that.

Great, thanks for the links and advice guys.

I do, on both the fixed/fixed wheel and the free/free wheel.