This is a Radiohead song about how Thom Yorke is subliminally planting ideas in your head like he did in Just when he said, “You do it to yourself,” and in “How to Disappear Completely” which is about Ego Death and not some dumbass shit Michael Stipe said. When you’re literate you can read the meanings behind popular music and entertainment.

[Verse 1]
I will shape myself into your pocket
Invisible, do what you want
Do what you want
I will shrink and I will disappear
I will slip into the groove and cut, me off
And cut me off

[Refrain]
There’s an empty space inside my
Where the weeds take root, and now I’ll set you free
I’ll set you free
There’s an empty space inside my heart
Where the weeds take root, so now I’ll set you free
I’ll set you free

[Chorus]
Slowly we unfurl
As lotus flowers
‘Cause all I want is the moon upon a stick
Just to see what if, just to see what is
I can’t kick your habit
Just to feed your fast-ballooning head
Listen to your heart

[Verse 2]
We will shrink and then be quiet as mice
And while the cat is away, do what we want
Do what we want

[Refrain]
There’s an empty space inside my heart
Where the weeds take root, so now I’ll set you free
I’ll set you free

[Bridge]
‘Cause all I want is the moon upon a stick
Just to see what if, just to see what is
Oh, the bird that’s flown into my room

[Chorus]
Slowly we unfurl
As lotus flowers
Because all I want is the moon upon a stick
I dance around the pit, the darkness is beneath
I can’t kick your habit
Just to feed your fast-ballooning head
Listen to your heart

He’s going to shape his message into your pocket and become invisible. These songs are coding things into your mind that will awaken you when you are ready to receive them. This happened to me. That’s how I know what he’s saying here. The last line: Listen to your heart.