Captaincranky

Is it the best solution? No, far from it.

You need to figure out how large is the interval you need to move the melody, and what key would it then be in.

Then you change the chord shapes to suit, and figure out on which fret to put the capo.

For example the I, IV, & V chords in the key of C major, open position, are C, F, & G.

Place the capo on the 5th fret, and play in C major using the shapes for the key of G major, G, (C in C), C, (F in C), and D, (G in C).

So, if you want to sing something in C#, (which is really called Db), then just capo the guitar on the 1st fret, and play in C. (C, F, & G). (This is in E standard tuning, EADGBe).

Because what you're doing, just makes the guitar sound like a ukulele. (I try never to capo above 3 0r 4, and even that sounds a bit thin.

I'll give you an example of a song I play, though I'm not sure you'll be familiar with it. (It's country).

Any way, the song is "Independence Day", by Martina McBride.

The song is in A major, but singing the vocal down a whole octave is a bit too low. So, we capo on the 2nd fret, and sing it down a b7th. The key is now B major.

Yes, I know there are times when the chord voicings give a song it characteristic sound. (The Stones, "Get off my Cloud", is mostly a standard E, A, B locked voice at frets 1, 5, & 7). But, many songs can have the chords inverted and not suffer for it.