How can i put my fire schedule in ical for the year?

So my schedule is something like this.

1 day on 2 off

1 day on 2 off

1 day on 3 off

1 day on 2 off

1 day on 2 off

1 day on 3 off

1 day on 2 off

1 day on 2 off

1 day on 4 off

the tour repeats every 31 days.

just don't wanna have to put in every day at a time,

thanks