Against kalista, Kalista is vulnerable to slows and CC. Try to lock her down at the beginning of the fight so she is unable to dish out lots of damage.

Kalista may stay in a side lane to split push. When she is not with her team, you can force a team fight or take an objective.

If you don’t know where Kalista and her Jungler are, they might be trying to sneak the Baron or Dragon. Make sure you have it warded at all times as she can take it quite easily thanks to her r.  Against kalista, Kalista is vulnerable to slow down and to the CC. Try to lock her up at the beginning of the fight so she can't dry up a lot of damage. Kalista can stay in a side lane to divide the thrust. When she's not with her team, you can force a team struggle or take a goal. If you don't know where Kalista and her Jungler are, they could try to sneak in the baron or the Dragon. Make sure you kept it at any time as she can easily take it thanks to her r.