What the topic says. Even if you're only able to test a specific area, that's a big help, so the next tester won't have to.
I'd be glad to help testing in return, especially if you yourself need a specific area looked at.
I have a walkthrough and cheat commands available, and I prefer to use a walkthrough (a bit short of time) as I think I'm pretty good at finding technical stuff & I know what sort of things get overlooked in the production process.