I personally believe that even 20 minutes of practice a day will get you there, but you are correct in assuming that its good to have goals and your time well thought out.

First, you need to determine what it is that you wish to accomplish. We all have different goals, so here is what a guitar player such as myself would probably like to focus on.

1. alternate picking
2. economy picking
3. legato
4. sweep picking
5. tapping
6. chord structures
7. scales/modes
8. jamming

Now after you have made a list of what you want to do, if it were me I would spend about 10 minutes on each. So, setting jamming aside, 7 x 10 = 70 minutes which is very manageable. Jamming can go for as long as you like.

If you want to get better faster, turn the 10 minutes into 20, 30 etc. For each technique I recommend working with no more than 2 - 3 exercises so that you stick with it and get those down pat. You may even want to limit yourself to 1 exercise here and there. Hope this helps!

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