Let's make this simple. DIRECTLY from the IMAC rules:

8.2.1. Turns
In aerobatic competition, a turn is divided into three parts:
1) Establishing the bank using a roll on heading.
2) The turn itself.
3) A roll back to straight and level flight on heading.
Let’s look at the turn during each of these three parts.
First, the roll to establish the bank. This must be a roll of between 60
and 90 degrees, it must be performed on the entry heading, and the
aircraft must maintain a constant horizontal line.

Once the roll is completed and the angle of bank is established, the
competitor immediately performs the turn. The turn must maintain
the established angle of bank throughout. The aircraft must also
maintain horizontal flight. The rate of turn is constant throughout and
the maneuver must be wind corrected so that, for instance, a 360 degree
turn will be a perfect circle. It should be noted that the wind
correction cannot be performed by visibly changing the bank angle.
As soon as the aircraft is on the exit heading, the competitor performs
another roll at a rate equal to the entry roll. Again, the aircraft must
maintain a constant horizontal line.

Downgrades:
a) The angle of bank established by the initial rolling maneuver
must be at least 60 degrees. Any less is a one (1) point deduction
for every ten (10) degrees.
b) The angle of bank, once established, must remain constant. Any
deviation is a one (1) point deduction for every ten (10) degrees
of deviation.
c) The rate of roll must be the same for the entry and exit rolls of
this figure. Any deviation is a one (1) point deduction.
d) The aircraft must maintain a constant altitude throughout the
figure. Any variation would be one (1) point for every ten (10)
degrees of change.
e) The rate of turn must remain constant. Any change would be
not more than a one (1) point deduction for each change. Note
that the rate of turn may appear to change in a strong wind,
when it really isn’t changing. The judges must always keep the
wind in mind and give the pilot the benefit of the doubt if there
is any question.
f) The aircraft must begin and end on the prescribed heading. Any
deviation is a one (1) point deduction for every ten (10) degrees
of deviation.