Repurposing sofa back rest as wall-installed cushion (?)

[athina]

Hello! New member here

I have an old IKEA Soderhamn sofa that has seen better days and is soon going to the tip, however I'm salvaging the cushions and back rest as they're as good as new.

The sofa:

I'd like to repurpose the back rest and use it as a soft sideboard (?) for a bed. I'm hoping to install the sofa back rest against the wall under the window sill as below - hence why calling it a 'sideboard' (although probably incorrect name)

Any ideas as to how I could start looking into doing this? Any advice would be much appreciated!

 

[big-all]

what power tools do you have and how good are your woodworking skills ??

 

[foxhole]

You could use these to mount the backrest to the wall.

https://www.amazon.co.uk/Headboard-Hanging-Interlocking-Brackets-FREEPOST/dp/B0788RNVV5/ref=asc_df_B0788RNVV5/?tag=googshopuk-21&linkCode=df0&hvadid=309947856166&hvpos=&hvnetw=g&hvrand=11829503061563115760&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006665&hvtargid=pla-697679519249&psc=1&mcid=cdf7ea1190383256a26cf8a96986b0c4