Proofread, proofread, proofread! And then, have your friends proofread. Grammatical errors are easy to make — just ask us; our editors are correcting ours right now (Editor's note: That's true!). But they can be a major turnoff for a lot of people. So go over your profile with a fine-tooth comb for their, they're and there, and your, you're and ur.
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