Pics of Valve Covers and advice?

[Corey'sgotachev]

I replaced old leaky valve cover gaskets a while ago and it stopped the puddle of oil under the truck.
...then the puddle was back.
...i retightened the valve cover bolts (?-hex head screws).
...then puddle stopped.
...then reappeared.
...then retightened...
etc etc

What should I use to tighten them for good? (Besides Loc Tite?)

Thank you for pics of your valve covers and advice!