My first attempt at a PhD was straight out of honours, in my early 20s. It did not go well. Despite being supported by some wonderful supervisors and meeting the academic criteria for enrolling, I wasn't doing it for the right reasons. I had the grades, I didn't have a full-time job lined up, and I enjoyed learning. I knew wanted to be an 'expert' one day - so why not do a PhD?
Because I didn't know what I wanted to be an 'expert' in.
Because I was young and inexperienced.
Because I didn't feel like I had lived.
After 9 months I became a statistic and dropped out. The following 10 years were filled with the life experiences I needed to figure out what I wanted to be when I grew up. Then, in my early 30s, I re-enrolled in a PhD and I loved it.
Being a mature-aged PhD student was nothing like my first attempt. I had lived my life (travelling, buying houses, meeting the man I wanted to share my life with). I had developed research skills (working in the private sector). And I had found my research passion (environmental behaviour change).
For me, the PhD was less of an educational experience and more an opportunity for self-indulgence. I knew I loved to learn and I knew what I wanted to learn about. So I crafted my research around my interests and skills - avoiding things I didn't enjoy (like interviews) and upskilling in areas I lacked formal training (like advanced statistics). As a professional researcher, I was excited to finally be in control of my own project.
I also used the skills I'd developed in the private sector to make my experience as painless as possible. My supervisors laughed when I brought them a detailed timeline less than 1-month after commencing the program. And I'm sure they laughed again (for different reasons) when I submitted 9 months earlier than my official deadline.
Whether you're fresh out of undergrad or returning to study with 10 or 20 years of experience, the best advice I have for future and current PhD students is as follows:
Treat it like a job: That means 7-8 hours a day, 4-5 days a week. It means attending relevant seminars, workshops, and other professional development opportunities. It means going to the office/lab and having water-cooler conversations with other students and academics. Adopt the title "Doctoral Researcher" rather than "PhD student". And, importantly, switch off when you're not 'working' and take regular holidays.
Set goals & plan early: Everyone does a PhD for different reasons. Write down your reasons and revisit them regularly to keep yourself on track. Set yourself goals and deadlines early. Things will change as you progress and that's fine. But update your plans accordingly.
Start at the end: It might sound crazy but start drafting your thesis outline as early as possible. Even just a skeleton or table of contents can get you thinking about the steps you need to take to get to the end product.
Write often: Writing is the bane and goal of all PhD students. But you can make life easier for yourself by writing as much as possible and keeping your notes organised. Keep two sets of notes when you're reading academic literature: 1) details on the methods & findings from the articles and 2) your thoughts and critiques of those articles. Every now and then (e.g. once a month), turn those notes into paragraphs. Then, when you start to write papers/chapters, turn those paragraphs into arguments and insights,
Write garbage: Garbage writing is better than a blank page. Cover the blank page in loose thoughts with terrible grammar. It's easier to fix a poor sentence than write a perfect sentence first-go.
My final tip is to be kind to yourself. You'll know when you're pushing yourself too hard. You'll know when you're slacking off. You'll know when you should take a break. You'll know when you should celebrate. Ask for help when you need it. And offer help when you can give it.