Sprints on your bike, well it depends on how far and how hilly your ride is, if it is on roads or on cycle paths, across parks etc. First make sure you are somewhere you can go all out safely
I'm not very specific about my running sprints, I just go all out for as long as I can maintain top speed, gasp for breath then repeat, however loads of people use Tabata intervals, which is 20 seconds on 10 seconds off, repeated 8 times to give a total work-out time of 8 mins, you can get tabata timers as apps for fancy mobiles.
To start with I would just pick a hill and hit it like a maniac, then rest, or sprint off from traffic lights, or a combination of both on the ride home (I like to sprint away from lights anyway, it keeps the car drivers on their toes). Just get as many bursts in as you can on the way home (once a week only or you'll kill yourself) to start with see how you go, get used to it, then work out ways to make it work with your ride home (you could do it on the way to work, but you'll arrive all sweaty, eeewwww)