Solo guitar is fun, but it's a lot more fun to perform with others. 2 guitars = twice the fun!
Unfortunately, it's not always easy to arrange a song to work as a duet - especially when you're first starting out learning the guitar and don't have the theory expertise to write alternative arrangements.
Here's 3 easy ways to prepare, practice and perform a guitar duet for your next cafe gig, party, exam or jam session.
Rhythm & Lead Guitar Delegation
90% of guitarists I talk to want to be lead guitarists.
Here's the shocking truth - all good lead guitarists are decent rhythm guitarists too.
But, when we're talking about performances, it makes sense to give the rhythm parts (chords, lower-range riffs etc) to the guitarist who either
a) likes playing rhythm guitar more or
b) is better at keeping time and following a song structure,
then give the lead guitar parts (solos, melodies and higher-range riffs etc) to the guitarist who either
a) likes playing lead guitar parts more or
b) is stronger at improvisation, scales and licks.
"We both want to play lead though!" I hear you egotists exclaiming. No problem - alternate who plays lead and who plays rhythm for each section of the song.
For example, you play chords in the chorus, and let your partner play chords in the verse.
This approach works best for rock songs or chordal songs that are simple to improvise over (eg. Am - G - C - Dm chords could be played by the rhythm guitar whilst melodies created using Am pentatonic could be played by the lead guitarist).
Find Alternate Voicings and Rhythms
Let's say you have a beautiful chordal arpeggio song that works great as a solo piece, but has no second guitar part.
If both guitars play exactly the same thing, it's kinda boring to listen to. It's also more obvious when someone makes a mistake!
Instead, try using different chord voicings.
For example, if the chords are Am - G - C - Dm, all played as open chords, have the second guitar play them as barre chords between the 5th and 12th frets.
For even better diversity, you can also mix up the rhythms. If one guitar is strumming, have the other pick the arpeggios of the chords.
This approach is just a starting point - you may end up writing an entirely different second guitar part just by experimenting with new voicings and rhythms, which is even better!
When in doubt, fall back on a pre-written Guitar Duet
Sometimes, it's easier to just pick a song that is already written as a duet.
Classical guitar pieces are very interesting to play and often have very nice melodic movement between the two guitar parts, as do many Spanish pieces.
As an added bonus, songs that have been arranged as solo pieces can be much easier to play when they are split into two, simpler guitar parts, which can make it easier for beginners to learn (we do this with quite a few pieces in our Classical Champion Guitar Course).
The exact song to choose will depend on your and your partners skill levels, but if you want an awesome example, Classical Gas (Mason Williams) is great fun with two players.
Another great one that come to mind are all the Al Di Meola "jazz" duets.
Working out these arrangements and deciding on who will play what is part of the fun of playing duets, so don't feel like you need to be super prepared to get started.
Just meet up with another guitarist, choose a few songs you both like and see what happens!