There are no specific rules other than those against touting and fake reviews. However there are “rules” of how to write a proper/useful review. You can have look at the reviews section and adopt a style/format that you find good or you may develop your own if you wish.
Anyway here is a brief guide:
1. You write a review in order to inform other punters about a WG but not in order to “promote” the girl because you think “she deserves it”. This is the most common mistake and there is nothing worse than a punter who assumes the role of a prostitute’s forum pimp.
2. Keep it balanced. Don’t use too many superlatives all the time but adopt a more critical-distant view. You may praise the girl but don't overdo it. Don't try to convince us to see the girl.
3. Don't end your report with “treat her well” and do not use ultra-fluffy soft porn descriptions like
this review. Remember you can be as fluffy as you wish DURING the meeting. But by the time the meeting ends you should quickly return to reality and remind yourself that this is just an illusion that you PAID to experience. The WG just wants your money ONLY. Anything you say suggesting you are deluded will be greeted with ridicule.
4. Do not boost about yourself in a review (your big cock, your “Cristiano Ronaldo” looks (as the stupid "PrinceofLDN" did
here), your fit body, that the prossie told you that you’re handsome, your luxurious car like
External Link/Members Only, your martial arts and cage-fighting skills, etc).
5. Write your review having the punter in mind. Answer the questions that you would want to typically ask about a girl that you are interested to meet for first time: (i) whether her pictures are authentic and accurate, (ii) what is her attitude during the meeting, (iii) whether her place is safe, discreet, clean etc (iv) whether she clock-watches or not, (v) whether she is rushing you or not, (vi) whether she provides all the listed services or she tries to avoid them, etc
6. Don't hide things that may put people off. You may downplay them if they didn't bother you but you must mention them. For example personally I don't care much about CIM so if it’s not offered I don’t see it as a negative. But I will anyway mention it as for others the presence/absence of this service may be decisive. Similarly for the appearance (having tattoos, piercings, saggy tits, full waist, some belly, stretch-marks etc), being smoker, speaking only very basic English, etc
7. Keep your review informative and detailed but also concise/condensed and interesting to read. Good practice is to use titles/sub-headings etc as if it is one continuous too long paragraph people get bored to read it.
There are many other points such as consistency etc but I think the above are the most important.