Beginning last Fall, I've studied and practiced the original Franklin Planner and modern Franklin Covey planning systems. One of the strong parts of their system is the master task list - you have a master task list each month. From the materials I studied, the emphasis is to get your important items into a timeline.
In setting monthly goals or objectives, I have observed that I am very sloppy with that large chunk of time an entire month provides. I know that I know that I need to do a thing, the thing is on the right lists all of the time, and then next thing I know that whole luxurious month of plentiful and abundant time is coming to a close. Oops.
There are week numbers throughout the year on many calendars for all 52 weeks. That doesn't really help me with my monthly planning.
Being very weekly focused, I like to think of months as 4 weeks. So I've added a few new notations to my system which have been very helpful.
At the beginning of each month:
On my monthly calendar, to the left of each week I scribble in Week 1 on the first row, Week 2 on the second, Week 3 on the third and Week 4 on the fourth.
On my corresponding weekly planner pages for that month, I write the same Week 1, Week 2, etc. at the start of each week.
On my daily pages, I write the same Week 1, Week 2, etc. on each Monday, the start of my working week.
Any other lists for "This Week" get the same week number notation as well.
This small and simple notation has helped immensely for me not to get too comfortable swimming in that deceptively large pool of a month.
I hope this gives you some helpful ideas as well.