A good place to start for an advanced student learning a new instrument? For guitar, the most difficult thing for most people is physical, making clear sounds with your tender fingers. Then it's the dexterity to swiftly move your sore fingers to different chord positions like in a game of Twister. You will eventually get fast but only after a month or two, your fingers have to build up strength and callouses. Lots of people give up before this happens, so it depends on your motivation. The reward is that once you get over that initial hump, it's a very versatile and fun instrument to play.