How to remove Oil Cap?

[SteveE]

For the past week the engine light has been permanently on and having had this problem before (where it turned off suddenly), I'v been waiting for it to happen again but unfortunately it's remained on.

So before I took it to a garage I decided to check my dipstick (yeah, I should have done this straight away) and low and behold the oil is almost non existent.

Armed with oil I'v been trying to take the cap off but I can't for the life of me figure it out. It's a 'clicker' cap with an yellow arrow point from left to right and I'v tried to press it down and click it off...press it down and lift it before it clicks but I can't do it.

Can someone possibly help?

[SierraYankee99]

Have you tried sliding it to the right?