I hoped everything went well so far.
Not sure if you know this but you could actually seek for legal aid (once) to help you draft a writ of divorce, state your claims, etc.
It is not wise to act in person unless you have some background in legal skills.
However, I could just give my pointers on how the layout of your claims could be:
1) Start off with a relevant header i.e. STATEMENT OF CLAIM FOR MAINTENANCE OF (your child/children name)
2) Address the legal issue here i.e:
"In pursuant to the divorce of (you and your ex), case reference no.(divorce case reference), I, (your name, NRIC) hereby state the following claims and requirement from the respondent/my ex husband (plaintiff and respondent are usually used when you are represented):
3) List down your claims and requirement/conditions with tags. e.g. i. ii. iii or 1. 2. 3.
4) End your letter with an appropriate legal footer like: "Unless the respondent is able to prove that the claims were unjust towards him, within 7 (Seven) days from the date this claim was submitted and made in court, in a written affidavit, I deem him agreeable with these terms and will lawfully abide to it and make out the payment for the claims duely and accordingly." (this is just an example)
5) Sign off with "Yours faithfully" signature and your name below your signature.
The above is just a rough idea on how the claims should or may be written.
Hope this helped (though it's a little too late)
Jameson - husband of malibu.