During each phase you do a different thing. Here is a list of what you do in each turn:
1- UNTAP: This is the first phase of the turn. During this phase you untap all cards, except cards that have abilities or spells on them which prevent this.
2- UPKEEP: This is the second phase of the turn. During this phase you pay all upkeep. ex. If there is any upkeep on a creature this is when you would pay it.
3- DRAW: This is the third phase of a turn. During this phase you draw a card from your library.
4- MAIN: This is the fourth phase to a turn and it is when most of the action occurs. During this phase you may do many things. You can play any card, but may only play one land a turn. You may also attack an opponent, but you may only attack once each turn. You may cast spells, summon creatures or play enchantments.
5- DISCARD: If you have more than seven cards and are done all things you wish to do, you must now discard down to seven cards.
6- CLEAN-UP: At the very end of your turn, all damage delt to creatures is erased and all spells that last untill 'end of turn' wear off and any spells/effects that happen at 'the end of turn' happen now.
