- Start in the past. If you have a lot of backstory to cover, might as well start in the past.
- Create two separate time periods. One for the main plot, the second to step back into. The flashbacks spring up when a point needs to be shown in order to make the next scene make sense or to fill in gaps before the next part.
- Focus on a single event to collect the flashbacks around.
- Skip them. Yes, yes, yes, we all think that those scenes are absolutely needed to tell the main story, but maybe not to the reader. They can appear sudden, needless, boring. Every story has a past to it, but it doesn't mean you have to show us it or bring it up at every relevant point in time. Sometimes, not showing the past makes the main story stronger.