A bar shift is not one activity performed for eight hours. It is three or four different jobs stacked in a fixed order, and most of them do not involve making drinks. Knowing the order is the difference between looking competent on your first day and looking lost.
Open
The opening shift is a setup job. Somebody counts the drawer against a starting bank and signs for it. Somebody cuts fruit, fills the garnish tray, juices citrus if the bar juices fresh, makes or checks the syrups, and stocks the wells with the bottles that get poured most. Beer coolers get restocked from the back, kegs get checked and changed, CO2 gets checked, and the ice wells get filled — which is heavier and takes longer than anyone expects. Glassware comes out of the dish machine and gets racked where you can reach it without looking.
The rule underneath all of it: everything you will need during the rush has to be within arm's reach before the rush, because there is no leaving the bar during the rush. A bartender who has to walk to the back for limes at 8pm has already lost the night.
Service
Service is not steady. It arrives in waves that are specific to the room, and the waves are the single most useful thing to learn about a new bar. A restaurant bar has a pre-dinner wave, a dinner wave driven by the dining room's tickets, a lull, and a late wave. A neighborhood bar has an after-work wave and a night wave with a soft middle. A club is dead until it is violently not.
During a wave you are doing four things at once: taking orders, making drinks, running the point of sale, and reading the room for who is next and who has been waiting. Between waves you are restocking what the wave consumed, because the next one is coming and nobody restocks during it. New bartenders spend the lulls standing. Experienced ones spend the lulls resetting.
Side work
Every bar has a written or unwritten list of tasks assigned to each shift that have nothing to do with the guest in front of you: wiping bottles, polishing glassware, filling wells, breaking down the garnish, deep-cleaning the drains, restocking the beer for the next shift. It is real work with real time attached, it is usually unpaid in the sense that no tips arrive during it, and how fairly it is distributed tells you a lot about how the room is run. Ask what the side work list is before you accept a job. The answer is diagnostic.
Close
Close is the part people underestimate. After the last guest leaves, the bar is broken down: bottles wiped and rotated, garnishes discarded or stored, ice wells dumped or covered, mats pulled and run through the dish machine, drains cleaned, speed rails emptied, coolers restocked so the opener is not starting from zero. Then the money: tabs closed out, the drawer counted down against the starting bank, sales reported, tips totaled, and the tip-out paid to whoever is owed it that night.
Plan on the close running well past the point the door locks. Depending on the room it can be an hour or two after last call. If your ride, your train, or your childcare ends at a fixed time, the close is the number you need before you take the job — not the posted shift end.
The handoff
Bars run on the assumption that each shift leaves the bar ready for the next one. When that breaks, it is the most reliable source of friction in the building. The closer who leaves the wells empty makes the opener's morning miserable, and the opener will remember. Being the person who leaves it better than you found it is the cheapest reputation you will ever buy, and in a job where the schedule is assigned by people who like you, reputation converts directly into shifts.
The trail
You will hear "come in for a trail." A trail shift is one of these shifts worked alongside someone who already has the job, partly so you can learn the room and partly so they can watch you. It is an audition conducted at work speed. Module 5 covers how to survive one; for now, know that it exists and that it is how most bar hiring actually concludes.
Ask whether the trail is paid before you agree to it. Both answers exist in the industry, the answer varies by venue and by state wage rules, and it is a normal question that a well-run bar will answer without flinching. If the answer makes you uneasy, your state's labor department is the place to take the question.