I make them 2 at a time. I have acquired a few 12oz and 20oz steaming pitchers. These make it easier to bang out all the drinks and do dishes later. I didn't buy them all at once but I am frankly surprised how many I have. I like the Barista Basics ones. You can get away with about 4-6oz of milk in a 12oz pitcher and 8-12oz in the 20oz. Caveat, I think my pitchers are 20oz, they might be 32
With that outta the way, here is what I do:
Pour the milk for both drinks into the larger steaming pitcher.*
Have an empty smaller pitcher on standby.
Make shot one, set it aside.
Make shot two, while the shot is pouring, steam milk for both drinks in the large pitcher.
Use "milk sharing" technique to pour milk between the large and small pitchers in sequence to make both drinks.
*having lots of pitchers means you can stage the milk for 6 drinks in 3 large pitchers and you won't have to do dishes / rinse things between rounds of drinks.
Look up "milk sharing." It takes practice. In the home, as opposed to the cafe, it can be very hard to develop a good technique and keep practiced. I get better around the holidays as I get more practice. Thanksgiving is a train wreck but by New Years I am dialed-ish.
Search the web for videos of Dritan Alsela. Lots to learn through observation.