The video gets a bit science-y, so here's a cheat sheet...
Start with a big blob shape that looks a bit like a potato (the vegetable of love)
Draw another blobby shape on top of the first blob, with 3 spouts coming out the top. Put little circles on the end of the chimneys to make them look round.
Again from the top of the blob add some tubes by drawing a bunch of curved lines and linking up the ends with little circles
Repeat the last step on the other side. A balanced heart is the key to success!
Starting from behind the tubes, draw a curved line connecting to the main blob. Do this on both sides. They look a bit like backpacks made of meat.
Add a couple more tubes to the bottom of the heart #tubelife
Add some wavy lines in the body of the heart to make big chunky veins filled with blood and other gross gunk
Fill in the gaps with some more wavy lines. Add to those wavy lines by drawing more coming out of them for that rooty-veiny-gruesome look
Finally, take a red colour and draw in as many drips and splats and splurges of blood around the heart and coming out of the tubes. The more you add, the grosser your heart will be! (Why not try adding some green slime too?)