How to install valve cover gasket correctly on a small block?

the type you have is fine but you don,t use any sealer on rubber. just take the covers off, clean them up good, take a small hammer and flaten the bolt holes out, clean the surface where the gasket goes on the head and pans, lay the gasket on the pan. if it don,t want to stay in place use some thread to tie the gasket to the pan then install it. don,t overtighten the bolts or you will warp the pans.