The best way to reduce feed costs is to reduce flock size.
The second best way is to free range in a large, biodiverse polyculture, supported by a high nutrient, well balanced commercial feed. Savings are seasonally variable, and risks of predation/injury/illness increase, of course.
The first two reasons are why, historically, flocks were culled coming into winter, then "Spring Chickens" were hatched as the new year began.
The third best way is to control waste - wet mash, pellets, or ferment. This may save 10%
Making feed at home is both very difficult, if you are interested in ensuring your birds have their needs met (yes, they can survive on less than optimal - but their production suffers. You don't save if reducing feed costs reduces egg/meat production of greater value). It is also, absent unusual circumstances, almost always more expensive than good quality cvommercial feed - producers enjoy economies of scale you will never achieve at home.
