Hi, thanks for your awesome question!!
My first piece of advice is the sacrifice your legibility IMMEDIATELY as soon as you start writing your essay.
A problem I used to have is... I would start my introduction with the fanciest muh'fkn writing you've ever seen. Curves here, joins there, some flamboyant ticks all over the damn place like I was tryna draft the next Declaration of Independence.
I'd really want to do a good job of my handwriting. Inevitably that sacrifices speed.
I think a lot of students do this.
THEN, 15 minutes to go, you realise you've only done 40% of your essay, and all of a sudden you're in a world of hurt. Then, BANG. You wrote too quickly, get the dreaded "can't read it, can't mark it" zero on your paper, then spend the rest of your days pacing Central Station decrying BOSTES and asking random passers by for spare change or an easily grippable pen.
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Instead... Just go HAM from the get go, but not "5 minutes to go" HAM. Just, "fuck my handwriting, I'm gonna do this quick" HAM.
In a paradoxical way, it actually takes pressure off, and it will make your admittedly low level of handwriting have a higher 'base' point. It's low, but it's consistently low from start to finish, and low to a point that you can still read it. If it gets lower than that point, as it might towards the end of your essay, that's when you're in trouble.
So I think that's one really good piece of advice. In the first minute, when you aren't under pressure... Write like you're under pressure, and you give yourself a whole world of extra time compared to your relaxed-but-shit-10-minutes-to-go-now-I'm-not-relaxedohgodwhatdoIdo friends.
So - focus on writing your essay, not on writing neatly. But make sure it's legibile. Find that point where it's legibile but you aren't trying to make it pretty. There's a big difference.
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Also, a high-level 800 words can achieve a lot. A skilled writer can get a lot out of 800 words. It's not really about the words, but about *how well you can hit the criteria*... And you can hit the criteria in 800, or you can hit it in 1000.
Obviously, the longer your essay is, the more chance you have of adequately hitting the criteria (some might thing), but really, if you're hitting the criteria extremely well in 800 words... You will get the high marks. (But an excellent 1000 words can certainly be better than an excellent 800 haha)