I got a new kitchen faucet installed with the pull down spray head. How do I hook up the water supply hose for my portable washing machine.

Not easily done with a pull down. You need a solid tube so you can screw the aerator off and a DW adapter on. Most pull down units have an inserted aerator and little or no clearance for the adapter. You MAY be able to remove the spray head and go from there but you would need to do this every time. You might want to reconsider your faucet choice.

Sorry but you just installed a square peg in a round hole, they are not compatible. ma is correct