That depends on your situation, and what issues you are addressing with the court. Only a lawyer can give you specific advice about what you should or should not say in your affidavit.
Affidavits are meant to outline facts – for example, they should describe ‘who, what, when, where’ types of information, and things that you have seen, heard, or have good reason to believe. It is not appropriate to put your opinions in an affidavit, or to use a lot of hearsay. Hearsay is information you heard from someone else, and did not know or see yourself.
If you are the applicant, you should include the ‘order sought’ in your affidavit, usually toward the end. This means that you will describe what order you are applying for the court to make. For example, if you are applying for a court order on custody and parenting time with your child, make sure you explain what kind of custody you are seeking (who the child will live with, who will make decisions about the child), and what visiting arrangements you want in place (like every second weekend, etc.). If you are applying for child support, specify the amount you are looking for, such as the table amount, or special expenses for child-care, etc.
NOTE: A judge may strike (not allow to be part of the court proceeding) an affidavit that contains evidence that is not admissible, such as certain types of hearsay, or inappropriate evidence – anything that they consider to be ‘scandalous or oppressive.’ They can also strike irrelevant material from an affidavit – ‘irrelevant material’ is information that does not have anything to do with your particular legal issue. For example, if you are applying for child support and are stating in your affidavit that the other party cheated on you, this is irrelevant – it has nothing to do with the issue of child support.
The following video was made available through the Public Legal Education and Information Service of New Brunswick and Family Law NB.