This is gonna look bad!!

I tried to top off my collant but can't seem to get the radiator cap off!! It is a 87 300E. The top part of the cap turns but not the actual locking mechanism. Am I supposed to push down and turn anti-clock wise? Or pull up? It's been a long time since I mass with the cap, as a matter of fact since the last time I replaced the aux water pump two years ago.

How do I open the darn thing? Please help.

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95 R129
04 Infiniti G35.5 BS
10 X204