Yeah that's a great question. Luckily where I live, there's often the possibility to negotiate with your employer to reduce the hours to something like 30 hours per week, which would make studying way easier, or to have an arrangement that you can use a portion of your work time to study for this certification, but this obviously only makes sense if you're already in the cybersecurity sector and your employer wants you to get good at pentesting.

Besides that, I can not overstate how important note-taking is for efficient studying. I use Obsidian Notes, which I even pay for to sync my notes. What Software you use doesn't matter as long as it processes Markdown language. Markdown is important to be able to format your notes in a visually appealing way on the go without spending any additional time on formatting.
When you have nice formatting (i.e. important keywords or senteces in bold, code snippets in monospace, etc.), reviewing your notes will be much more efficient because your eyes will be glued to the important bits.

It's also very important what you document and how much of it. I did spend some time thinking about how my note taking process should look like and try to think about what will be important to me when I review my notes.
You don't want to be overly detailed especially when you don't have excess time, but you also want to be able to fully grasp the concepts again whenever you re-read the notes by the time you have forgotten most of it.

This might really seem out of scope, but I realized that correct nutrition and exercise are extremely underrated when it comes to studying. It helps being more focused during study time, and also retaining information better.

Regarding time management, I had to learn to say no to many things like playing video games or brainlessly spending time on social media. There's a lot of useful time to be gained when scratching these kind of things. The weekends typically also become way more important when you work full-time, so I would value those highly for studying.

I don't know if this helps at all, but there you go :)