How do you indicate line breaks in a poem when it is written without actual line breaks?

Question

In English, if you have a poem, like

Roses are red,
Violets are blue,
Sugar is sweet,
And so are you.

and you need to write it on just one line (for reasons of space or whatever), you would write it like this:

Roses are red, / violets are blue, / sugar is sweet, / and so are you.

That is, you use a single forward slash to separate the lines of the poem.

What is the equivalent of this in Japanese? I know that in some cases, you can just omit the line breaks altogether, e.g. writing

古池や
蛙飛び込む
水の音

as

古池や蛙飛び込む水の音

But supposing you did need to indicate the line breaks, how would you do so?

Answer 1

Japanese doesn't traditionally use spaces, so a space will indicate a line break. For example,

八雲立つ　出雲八重垣　妻籠みに　八重垣作る　その八重垣を

Which, if choose to write it in rōmaji, is

Yakumo tatsu / Izumo yaegaki / Tsuma-gomi ni / Yaegaki tsukuru / Sono yaegaki wo

I will say, however, texts containing poems would almost always be written vertically, so the need to write a poem horizontally is rare.