Best to write your piece in Word or something similar, so that you can spell-check etc. Of course, this way all the writing is done off-line, as well. We have a Reviews section to keep some of our homegrown reviews for posterity. If it's a help, please feel free to contact grace, Azlan or me for further advice either before a performance or email a draft afterwards for comment and perhaps some reassurance. If you haven't tried your hand yet, why not give it a go for your own and our enjoyment.
All views are valid.
Include overall impressions. Put the performance in context. Include your own responses, and reasons for those responses. Keep a good reference book handy. Put aside and re-read after a break.