every now and
(every) now and again
Occasionally; sometimes. I don't travel often, but every now and again I just need to get away from the city. My mom has sweets now and again but mostly eats only healthy foods.
(every) now and then
Occasionally; sometimes. Josh does stop by the store every now and then, but I haven't seen him lately. I don't eat a lot of sweets, but every now and then I just need a piece of chocolate cake.
every now andthen/again
From time to time; occasionally.