Keep in mind that planning is not meant to cram more into your day but to simplify the routine tasks in your life as well as to schedule important or fun things that need to be done. With the goal of living more simply in mind, you will have more time for joy and connecting to your passion if you plan. What do you want to do more of? What do you need to do less of in order to free up some time? Plan for some fun seasonal activities and actually schedule them.
Look at what do you need to do every day to maintain your life. Create a daily checklist so things flow easily and you don't have to think about it. Eventually this flow becomes habit.
Create a weekly "to do" list for things that need to be done that week and don't overfill each day. Be reasonable about your expectations and remember to be gentle with yourself. If you get more done than you planned, celebrate!
Now it's time to deal with your goals. What do you want to accomplish in the next 3 months? Do you want to create a new habit? Do you want to focus on your health? Do you need to prepare for big holiday plans or life events? Break it down into baby steps. Pick 2 items for each of the next 3 months that you want to do. Then pick a focus for each week based on those priorities. It might help to focus you if you look back at the last 3 months and re-prioritize. Do the last set of goals still matter to you? Circumstances might have shifted and the old goals are no longer a priority. If they are still important to you, re-focus and decide on what the next steps are to make it happen.
Remember that the urgent tends to get in the way of the important and sometimes at the end of the day you wonder why you didn't get anything done. By taking time to actually plan, you will be able to accomplish more because you have a roadmap to where you want to go.