One thing I highly recommend to people with step-throughs is
Walnut Studilo's frame handle*. A little pricey, but my fave bike accessory. Makes "awkward" to carry bikes easier to handle!
*Wow the price has gone up quite a bit from when I ordered! Mine was ~$44 with mono. Now Mono is an extra $18. Obviously not needed, and you may find a cheaper alternative if you are crafty. This makes stairs so much easier to navigate!