I'm sure many of you have seen this done. I certainly cannot take credit for this great design.
I followed this YouTube tutorial posted by the user Dollface22772. It's fairly straight forward and not nearly as messy as I expected. I only ran into trouble when it came time to do the splatters. Blowing polish out of a straw (I actually used a hollow pen) isn't as easy as it sounds. You may need to experiment a bit to get the proper consistency. Be patient; it's worth it! You may find that mixing a bit of clear top coat into your red makes it easier.
I've seen this same technique done a number of ways. Some people like to use multiple shades of red for a more varied look. Personally, I think adding a few darker splatters (possibly using a deep burgundy) would be interesting. It would give you the look of more congealed blood. Extra creepy.
Also, don't go overboard with the splatters. I found it looks much nicer if you use them sparingly. Too much red and the effect is ruined.
I used Sally Hansen Polar Bare for my base coat and Sinful Colors Sweet Treat for the splatters. I deliberately used a cheaper color for the splatters because I knew there would be considerable waste.
So, what do you think? Are you doing to try this technique?