Back links and video embeds are key to ranking videos as well as social signals. So it makes sense to share our videos on social media sites, since this will invite possible likes and furthers shares which are all social signals.
There are social bookmarking sites such as Onlywire, which offer a platform to quickly share across multiple places at one time, these sites are good for building multi-tier backlinks (basically backlinks to the page with your backlink to the video on).
But in terms of ranking videos using social sharing, you can get great results simply using the share button underneath your Youtube videos and going through them one by one sharing your content across all your social profiles.
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