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Your guitar routine should depend on your playing style, level, and the amount of time it takes to play the guitar. Check out Steve Vai's 30 Hour Guitar Lesson. It's a bit extreme, but it has some great ideas.

Decide what type of guitar you want to be. There you can find out which areas you would like to work on. If you want to be a metal player focus on picking technique, muting, etc. If you want to play jazz work on music theory - things like chord relationship, understanding of harmony (this will take a few years). Choose 3-4 techniques and work on them 1 technique per day. For example, I'm a rock player who has a tendency to improvise. I'm trying to edit:

Mon & Thu: Alternative picking

Tues & Fri: legato / tapping

Wed & Sat: Economy / Sweep Picking

Sun: music theory

Now I try to work on three things in each session -

Warm up - very important. You will feel like shit jumping right into the exercises. 10 minutes of this should be enough.

Exercises - Record and work on exercises from books / magazines / videos. Try to do them all in the same key. There's no point doing an exercise if you can't do it in a musical context. This is discussed in detail in @ bluevoodoo1's post.

Jam - Play over chords / playbacks / with a friend and only use the technique you decided on for the day. This is my favorite part of the routine, and IMO the most helpful part. Try to spend the same amount of time exercising and jamming.

Take a day off every week. Use it to study music theory or write new music. Be creative.

Remember, this is only a guideline. Try to be consistent but make sure you don't burn yourself out by changing things regularly. Take a day off every now and then to learn a new song or just to jam. Any routine is pointless if you don't enjoy it.

I hope it helps.