Take a copy of your court order if you have one (this does not mean you are paying your child support its just a copy they might ask you for it is in no ways proof of Child support payments made). If you are getting your wages garnished take your most recent pay stubbs. Take the last year up to the most recent one. Once you have those collected and put in a binder, go down to the child support office that is handling your case and request a printed log of the collected child support payments they have received from your employer. Each payment you havr made to them will be logged there with the amount and date along with a name and date of birth of the children these payments go to. If you have a mutual agreement with the other parent you should take the letter you guys have this written agreement on make sure it's signed by you and the other parent with the date on it as well as the other parents ID or license and it must be notarized. Take with you a copy of that and also any proof of payments you have made. If it's a check or money order it should have in the memo part written u201cChild support da/a/te and namez of child(ren)u201d. If you have been giving the other parent cash you should take a letter from the other parent that is written up saying you have been paying her child support in the amount of u201c$the agreed.amountu201d and have that signed and notarized with a copy of her ID and her phone number and that should be sufficient. By the way these letters must be notarized buy an authorized notary.