#1
Here is how, dont complain unless you have a better way.

Until you tune your guitar to something symmetrical like major 3rds, 4ths, tritones, 5ths, or minor 6ths, which I have tried all of them, you wont be able to master your instrument. You NEED, let me repeat, YOU NEED the guitar to be tuned equidistant. Otherwise, intervals arent symmetrical over all the strings, which is completely insane. I dont understand why anyone would prefer their instrument to be out of tune like that. Once your instrument is tuned correctly, you can begin learning chord shapes. You want your shapes to work EVERYWHERE. Not just on one string. That is, if you want to be successful. Once you figure out how you want your instrument tuned, and once you spend a few minutes, aka days, aka spend some fucking time studying your instrument and learn this:

C E G B is a major7th chord. If you want to add a 9, you can lower the E to a D or you can raise the C to a D. If you raise the C to a D, you create D E G B, aka an Em7 chord, 3rd inversion (m7 as root). You wanted a Cmaj9, not an inverted Em7 chord, thus lowering the E to A D is the best option, creating, C D G B, aka a 1-2-5-7 Cmaj7 chord.

Same goes with 13th chords. Lowering the 7 to a 6, C E G A, creates an Am7 chord, 1st inversion. You wanted something new and fresh, thus raising the 5 to a 6 is the best option, creating a C E A B chord, aka a Cmaj13 chord.

11th chords work either way, but the catch is that they form pairs in 4ths/5ths. An Fmaj#11 chord by raising the 3 to a 4, F B C E, is the same as a Cmaj7, 2nd inversion, Cmaj7/G, with the G lowered to an F, thus making a Cmaj11/F chord, same notes as the Fmaj#11.

I've spent 10 years studying this shit EVERY DAY of my life. This is the BEST way. The best musicians would be twice as good if they followed my methods. That is the most efficient and most effective way of learning chords. Take it or leave it.