If you already have your pilot's licence, you already know how to plan. And your plan seems to back that. A couple of pointers to help you hone your planning skills. They were written with flight operations in mind, but the principles therein apply to all goal-oriented planning. Best of luck.
There are two fundamentally different approaches(81) pilots take to tackle uncertainty when they plan. One school teaches that it is better to generate several plans, one for each set of circumstances, test them one-by-one against the given set of circumstances, and then adopt the best one. The other teaches that it is best to devise one plan and test it against all circumstances. Is one method better than the other? Although they both satisfy the object of the plan, it is proposed that the first method places more importance on quality than what is needed. It is argued that the yardstick for planning should be the same as for all line decisions: adequacy.
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The difference between best and adequate is a difference between two levels of satisfaction: striving for a higher quality than what is needed is attempting overkill. And overkill is no more effective than kill but costs more. The difference between the best plan and an adequate plan gives the Air Carrier nothing while the method to generate it could cost him a delay, or worse, a missed operational window.
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Another area in need of attention while planning is flexibility. The first time we climbed into a cockpit we realized that rigid plans are DOA (Dead On Arrival). Therefore, plans should always be flexible. But how do we recognize and avoid plan rigidity? The following is offered as food for thought.
Rigid plans are recognized by their reliance on certainty. If any factor is less than certain, the plan should effectively address the uncertainty, both in isolation and in relation to other factors. Otherwise, the plan is rigid and useless. Warning signs of plan rigidity are assumptions incorporated in the plan as facts when experience suggests otherwise. For example, say, it is known that some airframes within the fleet consume more fuel than average. If the consumption of the subject airframe is unknown, a plan is rigid if it is based on fleet average. To be flexible, the plan must provide fuel for the airframe with the highest consumption. Note that it is not necessary to have experience with a particular airframe to detect plan rigidity: it is sufficient to know that some airframes in the fleet consume more fuel.
Another warning sign of plan rigidity is the legal "doctoring" of several factors to force a bad plan. While it is permissible to apply any value within an allowed range to accommodate operations near performance limits, applying marginal values to several parameters without taking synergy effect into account makes a plan rigid. Such plans cannot flex because the limits of their flexibility have already been reached. In other words, if they start out stretched to their limits, they are, in essence, rigid in so far as further stretching is concerned. Such practices eat up positive tolerances at the onset and thereby narrow operating margins. The net effect is a loss of tradeoff capability, the salient feature of good, flexible plans. (It should be kept in mind that the adequacy, referenced above, is not the same as minimum performance limits. Adequacy should include, among other considerations, all operational margins.)
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... good line plans always satisfy four criteria:
1. They lead to the objective,
2. They satisfy adequacy,
3. They cope with uncertainty, and,
4. They reflect command skills.
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(86) Schmitt & Klein, How we Plan, Marine Corps Gazette.
(Italicized text from: G.N. Fehér, Beyond Stick-and-Rudder, Hawkesbury, 2013, p. 203, 205-206, 209)