One of the ideas I have completely stolen from Michael Hyatt is to try to create my “ideal week” and get as close to it as possible. The basic idea is that you realistically allocate time for all the different tasks you need to do during the week at the optimal time for them.
So you might have two 30 minute blocks for managing your email at the start and end of the day, you’d also have the commute to work included and maybe picking your kids up from school every Wednesday and Friday afternoon when your partner can’t. Most importantly for anyone who has a variety of hats or is trying to do some creative work, you allocate yourself set time to do the tasks that can fall through the gaps. So maybe you have an hour block before the kids rise to do your writing, or a 30 minute chunk at night to write songs.