Take two...

Basically I finished soldering a Noisy Cricket amp and everything and plug in my guitar and nothing. It makes a popping sound when I turn on the amp, the light comes on, etc. I can even hear a tiny amount of hum and it changes when I move the pickup selector switch. But no sound from the guitar...

But the important thing to know is, when I plug in my computer/mp3 the amp plays that perfectly... whats up with that?

So I bought a multimeter. And now what?

I've experimented a bit. Its got a little sound thing that when the circuit is closed the multimeter makes a noise. So I started from the input jack to the speaker and it worked!

So what else can I do to check and see why nothing comes out of my speaker? I've read to use DC volts to check various parts? Where do I start?

Ok seriously? you got your thread closed and started another exactly the same? if he wasn't clear enough he meant ask the question in the thread you had linked in the one that was already closed, this keeps everything clean. So please ask in the thread you already have please. *reported*
LTD F-50
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'77 Harmony
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Epiphone Valve Junior combo