After a couple of seasons, I think I finally have this nailed.
At the start of the sowing season I had the problem of which seed to star and when. I know the information is on the packet but, each time we have to read the packet, sow the seeds and then put the packet back into the storage tin. Then go through the same procedure a week or two later.
So, to overcome this I obtained a small wooden box and divided it into partitions large enough to hold the seed packets. I then labelled the partitions January week 1, 2 , 3 and 4, February week 1, 2, 3, 4, March 1, 2, 3, and 4 and so on. I can now put the packet of seeds at the appropriate start point eg. January week 4. This way I know which seeds to sow and when and any seeds like carrots can be moved forward a couple of weeks to continue planting for a follow on crop. It works for me!