Bleeding brakes on any vehicle including a Haflinger is best done with two people.
Make sure you have new DoT 4 brake fluid available and top up the master reservoir before you begin.
There are brake bleeding kits available which use the air pressure in a tyre to turn the job into a one person operation, but with two people all you need is a suitable piece of clear plastic tube that fits the bleed nipples and ajar to collect the old brake fluid in.
As per the instructions above.
One person presses the brake pedal all the way down whilst the other person opens the bleed nipple. Then hold the pedal down whilst the bleed nipple is tightened. Slowly release the brake pedal so fluid can enter the mater cylinder and then repeat the the sequence of pedal down whilst opening the bleed nipple until all the air bubbles have disappeared from the clear plastic tubing.
Then move on to the next wheel.
Sequence is:- looking forward from the back of the Haflinger:-
Left rear, right rear, left front, right from assuming you have a right hand drive vehicle
Right rear, left rear, right front, left front if you have a left hand drive vehicle.
John