Took a bit of a liberty with the translation, rendering Zanmu's line as a direct play on the famous "Rapunzel! Rapunzel! Let down your hair, That I may climb thy golden stair!" More literally, she's bluntly telling Reimu something to the effect of "Well then, use this to come up to my side" with speech patterns that make her sound elderly.
If people feel that I've been unacceptably free with the translation I decided on, maybe try this instead:
"Be a darling and clamber up here, won't you? Use this!"