Her fringe would be pretty long if she were to let it down I think...

She'd arrange it smartly so they could be tied together at the back

①'s hair tips are facing upwards while the rest of the hair are seen below the band.

How her hair looks when let down

Probably similar to Ogurin

I understand it as her having 3 bunches of hair of varying length

First you grab ② and ③ and gather them into a loop before tying them up

The tips of ② and ③ will then be stored hidden inside the bulk of her hair (how though?)

Tis a huge mystery...

Do this for the other side and it's done