Writing a PhD thesis – “words of wisdom”

For those of you doing PhDs, whether your thesis submission is a few years away or a few months away, I thought I’d pass on some “wisdom” about the whole process (most of which is just how to avoid my mistakes…!) – from planning to mindset to little technical things. I read a lot of advice which sounded great but seemed very idealistic and sometimes just scared me – I’m hoping this is a bit more grounded and reassuring. Some of these tips may be broadly useful to other projects or pieces of academic work or writing, but it is quite focused on writing a PhD thesis, which I found a very different process to any previous academic writing  – partly just due to the length!