Order of a Turn

Order of a Turn:

1. Draw Phase (DP)
2. Standby Phase (SP)
3. Main Phase 1 (M1)
4. Battle Phase (BP)
5. Main Phase 2 (M2)
6. End Phase (EP)

Draw Phase (DP)

During the Draw Phase, the Turn Player draws 1 card from his/her Deck. This is the very first thing that happens during the Draw Phase, which means an opponent cannot activate a card before the Turn Player draws a card. Some card effects, however, such as that of "Hino-Kagu-Tsuchi", will activate during the Draw Phase, before the Turn Player can draw a card.

If the Turn Player's Deck Zone contains no cards when he/she enters the Draw Phase, and if he/she is required to draw a card, then he/she loses the Duel.

Trap Cards and Quick-Play Spell Cards may be activated in this Phase, after the Turn Player has drawn a card.

Standby Phase (SP)

The Standby Phase happens immediately after the Draw Phase. Some cards state that certain actions are to take place in this Phase, such as the effects of "Treeborn Frog", "Bowganian", "Legendary Fiend" and "Armed Dragon LV3" , as well as the Maintenance Costs for other cards, like "Messenger of Peace" and "Fairy Box". The Turn Player may decide in which order any of these actions are performed.

Trap Cards, Quick-Play Spell Cards and monster Quick Effects may be activated in this Phase.

Main Phase 1 (M1)

In Main Phase 1, the Turn Player may:

• Normal Summon, Tribute Summon, or Set a monster.
• Special Summon a monster(s).
• Manually change the Battle Position or perform a Flip Summon on a Monster Card, provided it was not Set or Summoned this turn.
• Activate effects, such as those of "Barrel Dragon" or "Blowback Dragon".
• Activate or Set Spell and/or Trap Cards of any speed. Quick-Play Spell Cards and Trap Cards cannot be activated in the turn they are Set.

If a particular monster wasn't Summoned this turn, the Turn Player can flip it face-down using its effect (such as with "Guardian Sphinx" or "Swarm of Scarabs"), and then perform a manual Flip Summon on it, since the rules state that only one manual Battle Position change may be performed per turn; Battle Position changes by effects do not count towards this.
After Main Phase 1 has ended, the Turn Player may choose to enter the Battle Phase. If he/she chooses not to, the player automatically proceeds to the End Phase (he/she may NOT enter Main Phase 2).

Battle Phase (BP)
The Battle Phase is the Phase in which Battles are conducted. A Battle Phase can be conducted every turn except the first turn of the Duel, after the Turn Player's Main Phase 1. It is split into four main areas:

• Start Step
• Battle Step
• Damage Step (includes Damage calculation)
• End Step

Main Phase 2 (M2)

After the Battle Phase, the Turn Player enters Main Phase 2. In this Phase, any action that could normally be performed in Main Phase 1 can occur, as long as the requirements are met (i.e. no more than 1 Normal Summon or Set).
In Main Phase 2, the Turn Player may:

• Normal Summon, Tribute Summon, or Set a monster if you have not already done so in Main Phase 1.
• Special Summon a monster(s).
• Manually change the Battle Position of a monster, provided that monster did not declare an attack during the Battle Phase, and provided that it was not Set, Normal Summoned, Flip Summoned, or Special Summoned this turn.
• Perform a Flip Summon on a Monster Card, provided it was not Set or Summoned in Main Phase 1.
• Activate effects, such as those of "Barrel Dragon" or "Blowback Dragon" if they have not been activated in Main Phase 1.
• Activate effects like "Cannon Soldier's" effect that can only be activated during the Main Phase, but can be used more than once per turn.
• Activate or Set Spell and/or Trap Cards of any speed. Quick-Play Spell Cards and Trap Cards cannot be activated in the turn they are Set.

If a particular monster wasn't Summoned this turn, the Turn Player can flip it face-down using its effect (such as with "Guardian Sphinx" or "Swarm of Scarabs"), and then perform a manual Flip Summon on it, since the rules state that one manual Battle Position change may be performed per turn.
The only cards available to skip this phase are "Flashbang", "Terminal World" and "Card Car D".

End Phase (EP)

Once Main Phase 2 (or Main Phase 1 if no Battle Phase was conducted) has been completed,the player proceeds to the End Phase. Any card effects that resolve in this Phase now take effect, such as "Change of Heart" or "Brain Control". The Turn Player gets to decide in which order any effect resolves. In addition, the Turn Player may also have to pay maintenance costs for cards such as "Clear World."
If the Turn Player has seven or more cards in his hand at this time, he/she must discard to the Graveyard cards until they have only six cards in their hand. This action is the very last thing to happen in any End Phase.
If an action is to be taken "at the end of the End Phase", such as the wear-off of the temporary 3000 ATK boost of "Theinen the Great Sphinx", it is, predictably, the very last thing to happen in this Phase before the Hand Limit Discard occurs.

source: wikia