It's the word on the tap.

What a Japanese person actually thinks
Completely literal. It's printed on faucets, water bottles, hydrant covers and swimming pool signs. If the Bruce Lee 'be like water' idea is what you're after, this character does not carry it.

Meaning

Literally: water
Actually: Water. Also Wednesday (水曜日).

Scores

Naturalness●●●●●

Correct and elementary.

Coolness●●●●●

Four strokes with nice symmetry, and nothing else going on.

Watch out

Nothing embarrassing lurking in here.

Get this instead

上善如水 jōzen mizu no gotoshi
the highest good is like water

From the Tao Te Ching — water benefits everything and contends with nothing. This is the actual philosophical statement people are reaching for, and it's a real four-character phrase.
流 ryū / nagare
flow; current; a school of practice

If the idea is flowing and adapting, 流 carries motion in a way 水 doesn't.

On skin

水

Orientation: either

Brush.