What is the best way to plan and sync voiceover? I'm working on an informational video which has some live action product shots, animation created in flash, a backgroud music track, and a voiceover track.

I've got total control over everything so I can edit the animation or re-record the voiceover (I do the voiceover myself). I just read http://www.directvoices.com/plaza/syncing-voice-over-to-video/ for example but it doesn't really go into specifics of how to do the planning or the fine tuning.

I'm trying to figure out what the best methodology is for planning and executing this. This is what I currently do but it feels very clunky to say the least:


Record Audio Track
Make animation in Flash with no Audio
Bring into compositing software (I use Premier CC2015) and do my best to trim and move tracks around. At times adding still frames to extend parts of the animation.
If I have to then I go back into Flash to make more animation to fill empty areas. I try not to have to redo the audio as much since its much more time consuming and would then have to start the entire syncing process over as well since talking isn't as easy as controlling a timeline.


There's got to be a better way to do this though, I'm just not sure what it is.

Should I just do the entire video and then play it while I record the voiceover? That would work for parts where the audio is short and the animation long. But is more difficult on parts where the audio is long and the animation is short.
In addition to @Mulvya answer I will suggest to use not Flash, but After Effects for animation, if possible. Then you will be able to make Dynamic Link to your AE project. Than will be easier to jump between applications.

But when you work with animation, you deferentially need to have voiceover first. Like in cartoon development.