Feet are upside down. The head and one foot are visible. After 30 minutes of labor there is no progress in delivery. If it is necessary to go inside the cow, be sure to wash gloves, chains, etc. with disinfectant. Use a lubricant such as mineral oil or newer cellulose products.
Soaps tend to irritate.
Excess force should never be used. When pulling, don't keep both front legs exactly together. Give straight backward and then downward pulls after the calf is in the pelvic cavity. Do not rush if calf is being delivered frontwards. Watch out for hip lock - rotate the calf 45 degrees if have hip lock.