Hello Hello. I am assuming you are talking about those blurry squares on the footage?

What format did you record it in?

AVI -> MP4 creates those square-blurriness

Unfortunately, that happened to me as well a long time ago and it was a headache. Try this fix. I am not sure it is the best, but it gets rid of the squareness. When you drag your raws into sony vegas and done editing it, render as wmv. then upload to youtube as it is. Youtube's format is MP4.

AVI render as WMV then upload to youtube (which automatically changes to) MP4

However, whenever you change the format, there is a slight quality loss.. however it is a lot better than having blurry squares. But that is the fix for now.
Also, if anyone has a better fix, please say so. hahaha.

You are most likely rendering it in Sony Vegas as low quality.

When you record/edit it, is it in good quality? (720, 1080p, etc.)

If, so, it's your render settings.

Check you render settings and make sure it is being rendered at the quality that you want.

The best thing I can say without further information, is try out what Lilikoi Juice said. I'm not sure whether what VatiWah said is true so I can't comment on that. But lilikoi's option seems a sensible one.