The best way is to tig weld it. You could mig weld it also. But they both use argon gas for shielding. You could use a torch and a rod called an Aladdin rod ( http://www.aladdin3in1.com/index.htm ) It is brazing not welding if you use this. If it is thin I have seen people use propane torches with the Aladdin rod. Good luck!
Additional - What do you call argon gas? (hint - inert gas) Inert or noble gas is, helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe) and radon (Rn)