An email is a contract
Illustration contracts don't have to be complicated. Most of the time your client will send you a contract to sign, but for every other project, you need to protect yourself against clients that might take advantage of you.
Get it in writing!
You always want to have a written (email) record of what you have agreed with your client. If any problems arise later in the process you can refer back to the agreement to resolve any disputes.
Ask your client to agree to your terms by email.
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