Hi Emmy
just to add again the first few months things will be a bit more of a challenge. Especially if you were like a lot of us heading for longer times between periods.
If your seeing clashes then you have two choices.
1) you can delay start of the next pack to avoid the dates
2) as you start your next packet start with prog part (green tablets) first.
This would basically push out further by the number of green tablets you take the day when your next period would start (normally a couple of days after the last green one).
Its only after the green tablets stop that your period will start so by extending the amount of days you take them then this could be enough to sort out your clash.
Once you've adjusted for 1 month then just take the next pack normally.
Its similar to taking our BCP without a break and missing a period
Remember it might take more than 3 months to get your periods back into the "flow" (sorry for the pun) but try and give it a chance.
Hope that helps.