It's never too early to work on leash manners! (well, maybe before they've opened their eyes)
At this age, puppies usually like to stay with you and check often to make sure you're still there. You can use this to help leash train. Put her on a 5-6 foot leash, and you can give her as much slack as you want - maybe just hold the leash by the handle on the end. Let her walk, and whenever she even looks back at you, praise and reward big time for this. If she comes to you, that's even better. If she starts to pull on the leash (you feel any weight on the leash, it becomes tight), immediately stop walking and wait until she loosens the leash. Don't entice her to you or jerk on the leash, just stop walking and let her figure it out. When she loosens the leash, you can praise her and start walking again, but again, if she looks at you or comes to you, give that a big reward.
I would not expect her to be able to "heel" just yet, wait until she's about 6 months or so and has a little longer attention span. But in the meantime, following the above instructions will help you out a lot with heel when you teach that.