When you start your pump, tap Start on that step. Tubular keeps track of the feed. It doesn't control your pump.
It uses the rate you entered to estimate how much has gone in, so there's nothing to time or write down.
If you pause your pump, tap Pause here too, then Resume when it restarts. Paused time isn't counted.
You usually won't need Stop. Only tap it if the feed ends early.
When the planned amount is reached, about when your pump beeps that the dose is done, Tubular marks the step done.
It's an estimate. If your pump shows something different, you can fix it.
A flush doesn't need tracking. After you give it, just tap Done.
Both steps are saved. If an amount or time was different, tap Fix what was logged.
With Tubular Plus, pump detection can track feeds for you. See the Pump detection guide.