Objectives and Key Results or OKRs for personal development goals can be easily used. You just need to remember that the idea behind the methodology is to measure improvement. OKRs are not a to-do list. Instead it shows what you want to become. Or what skills to you want to become better at.
You set an Objective (be better at skill X). Then you decide on what level you want to reach and what are the things you need to do to get there. These factors will be your Key Results that show what you are doing on a weekly basis to move towards your Objective. Don’t forget that all KRs should be measurable and tie into the goal.
As a tool, OKRs can also be used for self evaluation. As OKRs keep you on the right track, make sure you don’t loose focus and remind you what the big picture is.
For instance, when learning HTML set a KR “Finish an online course” with % based metric. But it could also be “read 5 books on the topic.”
OKRs for personal development goals, like when using them in business, should be monitored weekly. You can use an OKR tool like Weekdone for that. And also, Weekdone is free for teams of up to 4 people.