How do you make the breath delicious? Try things out. Use your ingenuity. Use your imagination.

"One of Ajaan Fuang’s students talked about the time when he was meditating in a bus — he wasn’t normally that good a meditator, but for some reason when he sat on a bus he found it very easy for the mind to settle down — and the breath felt delicious. Well, how do you make the breath delicious? How does that happen? In other words, try things out. Use your ingenuity. Use your imagination."

~ Thanissaro Bhikkhu "Beginner's Mind"