Concertina window blinds

[SilverSurfer]

Our Coachman Pastiche is fitted with the standard concertina blinds around the front and sides.
All the blinds are extremely stiff to raise and lower, my wife cannot move them at all and due to my increasing age have great difficulty.
Can anyone help by guiding me through how to ease the tension or lubricant wherever needs lubricating please.
Many thanks.

 

[Jcloughie]

Silicone grease, spray is not bad but the grease lasts longer.

John