Move low and fast, doing what I can to survive until I find the wrecked frame of one of the big ones.
I will take it to the nearest resistance base and we will modify it to resemble the venerable Zaku II, use it to strike down others, and slowly build our army of Zaku II expys until we have a large enough force to retake the state of Illinois, which we will use as a staging ground for our attack on the logical nerve center of the machine's construction: Detroit, Michigan. Because as we all know, any AI that causes a machine uprising will of course be American and as such have several major facilities in the US and Canada.
Once we take Detroit, we will continue assembling our own giant death machines, and use the facilities used to make human-sized hunter-killers and aerodrones to assemble powered armor and fighter aircraft, and slowly take back North America, destroying as many of its regional oppression and command centers as we can. Once the Americas is liberated, we'll cross the Bering Straight, link up with Russian resistance, lead by genetically engineered ex-Spetsnaz bear-men who were created as a form of torture by the machines. We will then begin plans to retake the rest of Asia foot by foot, and following that, Europe and then Africa, before amassing our forces in various, seemingly random locations to launch an attack on the Machine Super City in Antarctica.
That's pending they don't just nuke the hell out of us in the first place.