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English: Major Scale Modes for Perfect Fourths (P4) Tuning (ie. EADGCF), Including all Easily-Fingered Triads and Triad Inversions (for lack of a better name, and because I've never seen such shapes before, I've coined the term "Snake Shapes" for these zig-zag triad shapes) and Including Seven Boxes for Scale Memorization, with Details on the Adjacent Degrees and Relative Ionian Root for Each Mode to Simplify Playing by Numbers - Each zig-zag "Snake Shape" in this diagram contains four fingerable triads (each triad contains three notes, a 1, 3 and 5 degree - a triad is the most basic chord). Playing by the numbers is easy with this chart. Let's say you want to play a I - IV - V - I chord progression. First pick out a triad from one of the Ionian snake shapes and play it. Since your next chord is a IV chord you will need to then locate a "4" degree on your Ionian scale. Your snake shape triad instantly identifies the 1, 3 and 5 degrees, and all other degrees are a whole step (two frets) away, with the exception of the immediately-adjacent degrees which being only a half step apart are next to each other on the fret board (in Ionian the only adjacent degrees are 3 & 4, and 7 & 1). So locating all of the degrees close by the triad you just played is relatively easy, and becomes second nature after a little practice. Since you know 3 & 4 are next to each other, just locate a 4 degree one fret up from the 3rd degree in the Ionian triad you just played. Now pretend that 4th degree is actually a 1st degree, for a Lydian (IV) chord and play the Lydian triad (from the Lydian snake shape) whose root falls on that string. You've just played the IV chord. Now recall that the roots of IV and V are a whole step apart and you'll realize you can move that exact triad shape, unchanged, slide it up two frets and you'll play the V chord. Finally you can return to your original I chord, or at any time for each mode/number you're in, if you recall the degree of that mode which corresponds to the Ionian root, you can easily transition back to Ionian (this is a second way you can transition back to Ionian (the I chord), so you don't have to repeat the first chord in your progression. From Mixolydian (V) the Ionian root is the 4th degree of the Mixolydian (V) scale, so simply locate a 4 degree (in Mixo, adjacent degrees are 3 & 4 and 6 & 7, so from your V chord's 3rd degree move up one fret on the same string and you've found the 4 degree, which IS an Ionian root - now play the triad shape from the Ionian snake shape whose root falls on that string and you've transitioned back to a (I) chord.

Now you may have noticed a huge bonus which is that the snake shapes for the triads for Ionian, Lydian, and Mixolydian are all identical! So you only need to memorize 1/3rd. Likewise, the triad snake shapes for Dorian and Phrygian and Aeolian are identical (Locrian is the odd-ball, with its own distinct snake shapes (color coded in green)). The snake shapes are color-coded to indicate that these snake shapes, for some modes, are identical shapes. This cuts down a lot on memorization.

Finally, although this technique is currently diagrammed/charted for Perfect Fourths (P4) tuning, where the guitar strings from low-to-high are: EADGCF or BEADGC, you can also apply the same concept to standard (EADGBE) tuning.