when it comes to the actual amount of bait i look at time of year, weather, how often the dam gets fished, the fish population in the dam, the general size of fish in the dam, the size of the dam, the amount of natural food, how long of a session im going for, your approach also plays a big part (mouse trapping, pva bag, feeding spot, etc)
when choosing what bait it depends on the dam (some venues are partical venues and others are boilie venues) and your approach (pop ups, criticaly balanced, bottom bait, stringers, clusters,single hook baits, etc). one can fish a partical boilie over a bed of particales or one can fish a boilie over a bed of chopped and whole boilies.
i normaly use a mix of tigers, hemp and maize for feed but also take a few selections of boilies with just incase.
i prefer mouse trapping as i hate over feeding.
in general you will feed less in winter then in summer due to the fish being less active and not feeding as much.
always fish with what you feed.