No consensus on best treatment/maneuver or order of their application.
HELPERR mnemonic - all maneuvers able to be performed by Emergency Physician, generally from least to most invasive
H call for help
E Evaluate for possible Episiotomy (or episioproctotomy) to increase the anteroposterior diameter of passage
L Legs flex (McRoberts maneuver) - best first option - hyperflexion of legs with mild abduction and external rotation (successful in 40% of cases)
P Pressure (suprapubic pressure, aka Rubin I maneuver) - apply pressure just proximal to pubic symphysis, either continuously or in rocking motion (in conjunction with McRoberts, increases success rate to 54%)
E Entry maneuvers - Wood’s corkscrew maneuver by applying pressure to anterior aspect of posterior<unk>  causing movement of<unk>  into more oblique position in pelvis or Rubin II maneuver - applying pressure to posterior aspect of most accessible<unk>  (anterior or posterior)
R Remove posterior arm by sweeping it across the chest and bring fetal hand to the chin, grasp and pull out of the birth canal and across the face (effective in up to 84% of cases)
R Roll on all fours (Gaskin position) - may relieve up to 83% of<unk> 
ALARMER mnemonic is an alternative to the HELPERR mnemonic and provides a slightly altered sequence of interventions:
A Ask for help
L Legs to chest (McRoberts maneuver)
A Anterior<unk>  disimpaction by suprapubic pressure
R Release posterior<unk>  (attempt made to deliver posterior<unk>  prior to anterior<unk> 
M Maneuver of Wood
E Episiotomy
R Roll on all fours
Shoulder dystocia
Emergent delivery
Cervical injury 
Umbilical cord prolapse
Infant scalp hematoma
Breech delivery
Preterm labor
Perimortem cesarean delivery