I swear by these bands. Mine are Starwood Sports bands, light/medium/heavy/extra heavy versions. Amazon has a handful of options, but if you're going to work out at home, I strongly recommend investing in a set! With these leg exercises I show in this video, I do 3 sets of about 15-20 reps each, depending on the exercise and how bad I want my buns burning the next day!

Ok, I was kind of being funny when I was talking about using my kids $hit to workout with--but then as I was filming this (while Jayden was actually standing in the walker...) I was like "oh dang, this is tough!!" so I decided to actually use the material! 
I honestly do incorporate my kids' toys into my workouts when I need to, but I use a scooter for most of these exercises when I'm doing my normal workouts. 
For my leg stuff, I do 3 sets of about 15-20 reps. For the abdominal exercises I show above, I usually do 3 sets of 10-15, depending on the burn. (Yes, I realize I'm probably beginning to sound a tad OCD to most of you with my "3 sets" of everything...but it does work!)
Form, control, and going at a slow steady pace are keys with most of these exercises that I do.

Most of my workouts are paired with either an abdominal or a back focus. Above I'm showing some of my favorite abdominal burners--of which I do.....drum roll please....you guessed it....3 sets of about 20-30 reps. Credit for a couple of these ideas go to my sis, @mik.fitness 
​After Jayden was born, I started slow, and not until about 7 weeks postpartum, with just a couple exercises focusing on abs. I did about 5-10 reps of each exercise, depending on how my lower back would feel during, and how controlled I could make it (so as not to further my abdominal separation) .