If you’ve been to China or Taiwan then you have no doubt entered the toilet only to find a Japanese squat-style toilet awaiting you. Putting aside the quandary of which way to face, the more important question is should you actually try and use it, well, as they say, “when in Rome…”.
This idiom is quite easy to break down into it’s constituent parts, and translate quite literally as “enter country/territory follow customs”. 入 (rù) being to enter, 境 (jìng) being a territory or within a boundary, 隨 (suí) means to comply, and finally 俗 (sú) is a custom.
nǐ qù zhōngguó de shíhòu, zuìhǎo rùjìngsuísú
When you go to China, it’s best to follow the local customs