A great spot by Guest - and a great song too! Analysed a little more simply, it's ABBA CDCDD.

There is a young cowboy, he lives on the range.(A)
His horse and his cattle and are his only companions.(B)
He works in the saddle and he sleeps in the canyons,(B)
Waiting for summer his pastures to change.(A)

And as the moon rises he sits by his fire,(C)
Thinking about women and glasses of beer.(D)
And closing his eyes as the dogies retire,(C)
He sings out a song which is soft but it's clear,(D)
As if maybe someone could hear.(D)

Goodnight you moonlight ladies,(E)
Rock-a-bye sweet baby James.(F)
Deep greens and blues(G)
Are the colors I choose,(G)
Won't you let me go down in my dreams?(F)
And rock-a-bye sweet baby James.(F)

A dogie, dogy, or dogey is a cowboy's name for a stray or motherless calf. It's derivation is uncertain, but lots of colourful explanations exist.