Same advice as always -- dress appropriately, smile, be friendly to people. And cross your fingers that there are no 1Ps or 1Ks on the flight -- they'll almost certainly trump you for an operational upgrade.
I've found asking a discrete question when I check in like "What's the load tonight" helps as well. If the flight is oversold, I typically volunteer my seat for VDB and hint at an operational upgrade at the same time. I often get at least one of my wishes!
Good luck, enjoy AMS.
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