I got this wah for christmas and am looking to get a good Slash wah

Mainly from the song Slither by Velvet Revolver

Any advice, settings, tips, or anthings else that would help?

Tweak it until you have the sound.
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At the risk of sounding condescending, I should point out that there's only two knobs to adjust and one of them isn't all that tweakable.

Just noodle around with it for an hour or two and you'll get the hang of it.
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