I went back to work when my ds was 7 months old. I worked 4 days a week with a full-time nursery place (as it cost very little more than 4 days a week) which gave me some breathing space if I needed to go to the hairdresser etc.
When he was 2 I changed jobs to full-time but was able to work from home from time to time.
A year later I was made redundant from that job and got another job full-time in an office which was ok but it was stressful with the pick-up as I could never rely on the trains to nursery but usually I made it on time.
When he went to school I cut my hours to 4.5 days a week so I could do school pick-up one day a week and my dh changed his hours so he could do it twice. I found a childminder for the morning drop-offs and two pick-ups a week. I changed jobs again shortly after he started school, and worked in London, but was able to work from home one day a week so was then able to take ds to school one day a week as well.
The school then introduced a breakfast club so I was able to use that in place of the childminder for a couple of the mornings. And sometimes there were after-school activities (only until 4pm but gave us more time to get home).
In 2012 I changed jobs again and worked part-time locally, so by then I needed one drop-off a week and two pick-ups.
Since mid-2013 I have worked from home, one day a week in London and so cut the childminder to one drop-off a week so that I could get an early train. Since September he's at secondary school so I don't need anything and I just work around him when I need to go to London and my husband still does 3 long days and 2 short days so is home early twice a week.
Holidays - childminder two days a week, and things like local football coaching camps. Occasionally my mum has helped out (but she doesn't live locally although one time she did drop everything and came to help when ds was ill), and my husband has done at least one day a week in the holidays. I draw up a grid each year of all the holidays and gradually fill in the days until I've filled everything in with someone or something. Nowadays it's much easier as ds is 12, I work from home and he just entertains himself. Also our local leisure centre runs lots of pool-based fun sessions which he can do for a couple of hours, although that only works because I work from home.
Anyway I hope this gives you an idea of the different options and the fact that things change. And dads should do their fair share.