I'm a beginner blender user and I'm trying to do some of those famous shape such as donuts and I'm trying to make the shape of dripping icing, but when I use snap it intersects with the other part. How can I prevent this problem? Although most of the videos use it normally without any problems. I could make the donuts shape and I made the icing but I need to make the drip.
I find using closest edge or vertex is much easier to control than "snap to closest face". You can place your mouse cursor near the edge/vertex you want to snap to and an orange circle lets you know where it is about to snap to. If it is a complex model with lots of close together edges and vertices it helps to zoom in as much as possible to make selecting the correct snap point easier.
Also, selecting "closest", "center", "median" or "active" can yield dramatically different results depending on your geometry. Its not a bad idea to try each setting when you first use a new tool to see how each performs differently.