How do you make muscles looks realistic because I have tried and they look nothing like a real persons muscles. Could someone please help me and tell me what tools to use to make the most realistic muscles.
All of the the tools, actually. That's because there are all kind of muscles on a body. However, once you have a decent basic proportional model you could use Draw in Clay mode to nicely layer muscles. Crease helps with, well, the creases between muscles, but be careful not to exaggerate it too much. It takes a great deal of studying to figure out what muscles have to look like. Check out body building images on google, but make sure you understand the lighting so that you can read the muscles properly. It can be deceiving. You also probably want to stay away from Inflate, because it's not as helpful as you might think, easily corrupting your geometry.
Draw(clay) Crease Grab for careful nudging
No tool turns you instantly into an artist, though, so you got to give yourself time, too! So your best feature is "Patience" and "Focus"!