From Mastering Pasta by Mark Vetri
2 cups semolina flour
2/3 cup of room temp water
1/2 tsp of salt
Unlike egg pasta this one is easiest to mix in a bowl, not a fancy egg nest. Add the flour and salt to a bowl, pour water and stir with a wooden spoon (the dough won't stick to the wood). It should form a shaggy ball of doughy pieces, but still look kind of dry.
Dump the dough and any remaining flour onto the tabletop and press the pieces together until they begin to resemble a ball. Work the dough by flattening it with the heel of your hand, picking up half, then folding it over again. I rotate it 90 degrees each time. The sequence goes like this: turn the dough, lifting half, fold and press. Do this until most of the flour has been picked off the table. Then set a timer and knead for at least 5 minutes and up to 15.
Here's a video of how I knead dough, notice at this point how smooth it is, I've picked up all the additional flour. If your dough is super sticky feel free to toss a little more flour on, or if its dry drip a little water in. Humidity can effect how dry or wet your dough is, so if something feels off go with your gut and add more water or flour.
Wrap tightly in plastic wrap and let rest for at least 15-20 minutes. You can refrigerate your dough at this point, just make sure to bring it up to room temperature before shaping any pasta. (Honestly though, in the time it takes to come up to temp you could definitely just make a new batch of dough)
Kneading the dough activates the gluten in the flour; this is what gives the dough stretch later. Pasta is much more forgiving than bread, you don't really have to worry about overworking it. Most recipes recommend a longer knead (15-20 minutes) but I've found that 5 minutes of real deal kneading gets the job done. The rest time is crucial. Two big things happen, the flour particles get a chance to become fully hydrated and the gluten network you've just built up by kneading gets a chance to relax. Your rested dough wont spring back if you poke it, and will be softer and more malleable. If you've ever tried to make pasta only to have it just spring back when its rolled it probably hasn't rested long enough.
Now is when the fun begins! Time to shape your dough!