From Wikipedia: “Alla prima (Italian, meaning at first attempt), is a painting technique, used mostly in oil painting, in which layers of wet paint are applied to previously administered layers of wet paint.”
In a nutshell, you complete a painting in one sitting, while oil is still wet. Something that can be a nightmare at first, because colours won’t “stay still” and will keep mixing together. If you put wrong colours in the wrong place you’re going to have a hard time – yellow is an especially bad choice here.
A good start was with easy subjects, using monochrome or very few colours, to minimise complexity and headaches. I did the 2 below, and it’s something I want to go back to. Especially as it forces me to adopt broad strokes, fast, and more confident lines, and you’re done with a painting in a few hours vs a few months!