2. Budget. Reassess your budget. Over estimate. Triple check everything.
A good calculator and some mental maths skills go a long way too. Just because you used to be good at maths, doesn’t mean you still are. And just because you did double check it with a calculator, doesn’t mean it’s right. If you forget to add $500 for food costs into your mental maths, and consequently forget about it when checking things with your calculator, you will still be out by $500. Even if you don’t realise it right away.
Make sure you know two things in particular; how much money your visa requires you have and how much the other stuff you might need for your visa will cost. For example I had $2000, for my visa I needed a letter confirming my accommodation, for that I needed to pay a $1000 deposit. That left me with $1000. Which is not adequate. At all.
Thankfully my parents came to the rescue, with a letter saying they would support me financially. I had my doubts, but was quickly told that letters are legal documents. I didn’t know that. And my doubts were ill-founded anyway, as within a few days I received a phone call saying my visa had been approved.
They spelt my name wrong on the sticker, so I’ve had to send it back, but the point is it’s approved. No thanks to my poor mental maths.