Via euro2008.com:

Draw procedure
Under the draw procedure, host associations Switzerland and Austria are automatically qualified and will be allocated into positions A1 and B1 respectively. The other 14 teams will be split into four pots. Pot 1 will comprise the reigning European champions Greece, if they qualify, as well as the nation with the highest coefficient. The other teams will then be placed in the three remaining pots, based on the coefficient obtained in the qualifying competitions for the 2006 FIFA World Cup and UEFA EURO 2008™.

Filling first positions
The draw will start with Pot 1 in order to fill the first position in each group. A first ball will be drawn from Pot 1 and the drawn team placed into the first position in Group C. Thereafter, the second ball from Pot 1 will be drawn and the respective team will be placed into the first position of Group D.

Draw continues
The draw will then continue with Pot 4 and end with Pot 2. A ball will be drawn from Pot 4 and placed into Group A. In order to determine the position of the team within the group and the fixtures order, a ball will be drawn from Pot a (either A2, A3 or A4). Moving to Group B, another team will be drawn from Pot 4. Once again, to determine the position of the team within the group, a ball will be drawn from Pot b (either B2, B3 or B4). The same procedure will be repeated for Group C and D (in consecutive order) until all balls from Pot 4 have been drawn and positioned in each group. The same procedures will be followed for Pot 3 and Pot 2.

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