So, my neighbor asked me if I could teach guitar to his kid, wich I accepted.
But I'm not sure exactly were to start
I mean, I have a good idea of were to go, but if you guys could help me on what the most important points are etc. it would be appreciated, there's so much things and I just want to make sure I don't forget anything
Don't be one of the people who don't teach theory to a student please...
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I'd start with helping him/her understand the 12 notes (A to G#) and the chromatic scale. Then go into come basic chords. That's what I was told to start with and it worked pretty well. I'm no teacher but talking to friends who were learning how to play guitar found things a lot easier once I helped them understand the 12 notes, their locations on the guitar, and root notes of chords. A friend who was taking a guitar class at our university was having trouble memorizing chords until I told her about root notes and it clicked for her right away as she complained that the teacher should have told her this before ever trying to get her to do a G chord.

Once that's done, different scales and other chords, i suppose.

And yeah, like KingofDudes said, teach theory... I have been self taught, been playing for 15 months and I didn't start off learning theory and I'm now trying to teach myself it with pretty much no personal, interactive help and it's rough.
First half of the lesson with theory, second half with songs that apply the theory. That way they get the best of both worlds.
See where the student is musically first. PG talked about this, and I always use it with my students; play something on guitar. Just something percussive, like a "scratched rhythm" on muted strings, usually in 4/4 with a tempo not too fast. Then watch and see if he can play something over it. You'll get a good idea of what he knows after 10 minutes or so of doing that.

Also you want to teach in the right order. For example, major scale would come before triads. Notes would come before chords. Steps would come before scales, etc. And don't forget to include the mechanics of the instrument itself. Teach him how to hold it correctly, keep the wrist at a correct angle, etc.