There are 2 hats, 3 scarves, and 3 pairs of mittens

Question

How many different combinations of 1 hat, 1 scarf, and 1 pair of mittens?

How would I solve this, other than writing out each combination?
Could someone please explain how?

Answer 1

2*3*3 = 18

You could make a tree

--- x
- x x
--- x

--- x
x x x
--- x

--- x
- x x
--- x

--- x
- x x
--- x

--- x
x x x
--- x

--- x
- x x
--- x

Answer 2

--- m
- s m
--- m

--- m
H s m
--- m

--- m
- s m
--- m

--- m
- s m
--- m

--- m
H s m
--- m

--- m
- s m
--- m