There are no special rules for playing free online slot machines. If you have played in a casino and have spent some time at the slot machines you can play the free online slot machines too. The rules and regulations of the free online slot machines are the same like that of their real counterparts.
The only difference is that one should not look out for any slot for feeding money to the machine. These slots games are free and neither do they expect any money nor do they payout any money. Apart from that one can find all the fun associated with slot machines when they visit online gambling portals to try their hands and luck at free online slot machines.