come up on the right side of the rail, and basically if its set up urban style than you can basically just step onto it, bend down, and grease it. it may take a few trys but just go for it
remember that when you pop you arent gonna land on the rail for a ways down, so you arent really jumping up the entire height of the rail, assuming this is a down rail
go on with ur skis parrales with the rail, this way u will be able to slide all the way to the end much easier than if u came in on a angle. at least this helped me alot