my noobie 2cents...

1) pre-flop, 3-bet like you gotta pair ... esp oop for the rest of the hand. I'd go to .35
2) I'd psb the flop... which would be a around .70 (loose maths...)

You give no reads. So if he still flats you he could have a lot of stuff... 6x, TT, AK, AT,KT,QT, JT, KK, AA, JJ (with no reads can't assume he'd raise you here...) or a flush draw off of Kx, Qx or Ax (AQ, AJ) sooted (or some other diamond suited connectors or gappers...)

When the turn drops, you're now losing to a pretty big part of that range. Flush draw hit, Kx hit, TT or 6x is still beating you. you're ahead of some of the Tx hands, JJ and crap. Plus you have only two outs to improve.

Without reads, I will prolly bet/fold around .8. Might be enuff to kick him out if he's not holding the flush and fold out JJ and Tx hands. If the River bricks, I'd prolly check/call a smallish bet. Much else I'm folding ... he likes his hand and you've only got a 2nd pair. But I am a nit.