How do i set my clock on my pioneer deh-p7800mp

Here is the link to your manual:
http://www.pioneerelectronics.com/vgn/images/portal/cit_11221/310077279DEHP7800MPOperationManual.pdf

Setting the clock
Use these instructions to set the clock.
1 Use MULTI-CONTROL to select Clock.
Clock appears in the display.
2 Push MULTI-CONTROL left or right to
select the segment of the clock display you
wish to set.
Pushing MULTI-CONTROL left or right will select
one segment of the clock display:
Hour—Minute
As you select segments of the clock display
the segment selected will blink.
3 Push MULTI-CONTROL up or down to
set the clock.
Pushing MULTI-CONTROL up will increase
the selected hour or minute. Pushing
MULTI-CONTROL down will decrease the selected
hour or minute.
Notes
! You can match the clock to a time signal by
pressing MULTI-CONTROL.
— If the minute is 00 to 29, the minutes are
rounded down. (e.g., 10:18 becomes
10:00.)
— If the minute is 30 to 59, the minutes are
rounded up. (e.g., 10:36 becomes 11:00.)
! Even when the sources are off, the clock display
appears on the display. Pressing CLOCK
when the sources and feature demo are off,
turns the clock display on or off.
Turning the clock display
on or off
You can turn the clock display on or off.
% Press CLOCK to turn the clock display
on or off.
Each press of CLOCK turns the clock display
on or off.
Note
Even when the sources are off, the clock display
appears on the display. Pressing CLOCK when
the sources and feature demo

Cheers!