First you begin with the amount of blood they had from the last session. Unless they need to feed off vampire blood, it is assumed that they are capable of maintaining their current blood supply minus any healing required.
Then we move onto the typical Attribute + Skill roll to reflect their hunting technique and gain the successes in blood. Record both the bonus and the actual number on the dice to check for feeding mishaps.
Add the bonuses from certain disciplines that synchronise with that skill (+1 blood for the use of Majesty, Dominate or Obfuscate).
Subtract a -2 penalty for any feeding restrictions taken (not including animal or human basic restrictions but does include attempts to avoid the Daeva bane triggering).
Add the Rack bonus (ranges from 1 to 5 with all racks beginning at 2 at the start of the campaign) as a single use blood bonus. This encourages PCs to build up their own racks and perhaps undermine the racks of other people. Since my Adelaide is divided by gloom patches which crisscross the city and can wipe out an errant vampire attempting to cross them … rack accessibility becomes very important.
Add +2 bonuses for the custom Coil of Ascetic at both the Binge Drinking and the Carrion Feeding levels (presuming they can eat their victim's carrion). Having to use Feeding Below One's Beast overwrites the use of Binge Drinking as they cancel each other out.
Add the feeding grounds bonus as a single benefit for the first feeding check.
Use Herd only if there's a need for it. Otherwise do not use Herd so that they can sell them later on or call upon them during the session.
If more blood is required, ask the player if they would like to spend further downtimes on feeding.
A very complex system but one that makes the Rack Building Mini-Game, Herd and Feeding Grounds more important. Bear in mind, also, that the current city law entitles vampires to a block of feeding grounds per rank of status which is enough to provide a feeding check bonus on the Valued (+1), Respected (+2), and Admired (+3) levels.