Two pieces of advice that someone finally told me a little later than I wanted: Let #2 cry a bit if #1 really needs your help. #2 doesn't know any different, but 1 is used to getting his needs met. The other is to have someone watch #2 while you get 1 on 1 time with #1 for at least 30min-1hr per day.
I found that baby-wearing was so helpful. My son didn't take naps, he took cat naps (20 min.) at a time, if he were laid down. If I wore him, he was content for his 20 min. nap and for much longer when he was awake. This also freed me up to play and read to my dd.
The most challenge was getting dinner ready. I didn't like to wear baby while at the hot stove/oven. I felt it wasn't the safest way to go and dd wanted attention, too. What did help was either the bouncy chair nearby for ds and dd helped prepare some of the dinner, if possible. I would try to have her do as much as possible for 2.5.
It is harder and I did it mainly by myself with little help, even in the evenings, from hubby. He is not a hands on parent.
Good luck to you and try to enjoy each moment. The time slips by even faster with two. It does get easier and they are a joy.