Any bookings index watchers could do worse than follow Paraguayan official Carlos Amarilla.
He is famous for getting the cards out early so as to stamp his authority on the game which gives a good chance to walk away with a guaranteed profit on the spreads or in-running fixed odds markets.
Can't see yet his first match, need to keep checking for that.
Traditionally First Round matches rate higher as more restraint is shown in QF and SF games as neither FIFA or the players themselves want a ban in latter stages.
Brazil v Portugal is usually like an Old Firm game for bookings and with the extra spice the WC brings...need I say more.