The standard grips this chord is usually shown with.
C#alt is C#, E#, A, B and D, a altered dominant. The shape this page opens on is written x43021, lowest string first.
There are 9 common shapes for C#alt on the guitar, and 22 derived voicings in 3 families.
The common shapes, written lowest string first: x43021, x43x23, x45063, x43663, x4566x, 9-8-x-10-8-9, x-x-11-10-8-9, 9-10-11-10-x-9, x-x-11-12-14-13.
Shell. Root, third and seventh: the guide tones fix the quality, so the fifth is dropped. That is what leaves a string free, so pick a tension to put on top. C#alt has x4343x, 9897xx, x-x-11-10-12-10, x4x465, 9-x-9-10-10-x.
Rootless. The root left to the bass player. Frees a finger for a tension. C#alt has xx0201, x2323x, xx3435, xx7767, x-x-9-10-10-10, x-12-12-10-12-x, x-x-12-14-12-13, x-14-15-14-15-x.
Open string. An open string left ringing against a fretted grip. Because it costs no finger, it sounds a note the closed shape has none left for -- a tension on top, or a pedal root underneath. Either a familiar grip with open strings added, or a shape so sparse the open strings carry the chord. These belong to their key rather than to a shape, so D, A, G and E have many and Eb a handful. C#alt has x00067, x0046x.
Tensions. A shell of C#alt, root, third and seventh, leaves a string free, and the tones that belong over it are the #11 (F##).
The common shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.
Shows each chord the way this style would voice it, and marks which of its alternatives belong to the idiom.