Question re: slo-mo in fanvids

I'm going to be making a video probably this week. Well, two versions of it. And I might have to use some slo-mo in the second version of it due to the nature of the song. I've never used slo-mo before and was wondering if any of the oh so talented vidders on my f-list had any advise for dos and don'ts of slo-moing. If there are any. I just want to make sure I get it right if I need to use it.

Thanks!!

Hal Icons

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( HAL ICONS! )