Do you know why it's important to have a design contract? As a graphic designer, a contract is important because it's not only a promise to the client regarding what will be given to them, but also serves as a protection for the designer. So what do you need to include to ensure you're protected? Here's some ideas:
Project overview. Write out exactly what you as a designer are being hired to complete, this way there will be no confusion and extra work beyond what was agreed can't be snuck in.
Schedule. Include an agreed upon start date, and how long you are being contracted to work for. In many cases, it might be difficult to accurately state how long a project will take, so I personally have in my contract that I will continue to work until the project is completed with an estimated timeframe; but this comes with conditions such as the number of revisions a client can have, and the number of concepts I will present before taking one to completion. More on this later!
Payment. I ask for 50% of the total fee upfront to ensure the client is serious about the project. Only after receiving this will I start working!
Extra work or revisions. If more work or revisions are required on top of the agreed upon amount, I include in my contract that the client will begin paying my hourly rate. This relates back to my points on 'schedule'.
Extra expenses. I include in my contract that the client is solely responsible for extra expenses, such as those for font licenses, stock imagery, and other commercial licenses.
Invoicing and delayed payment. To ensure a client pays the rest of the fee on time, I state in my contract that the outstanding money must be paid within 14 days of sending my final invoice, otherwise I will charge interest on the unpaid amount, at a rate of 10.0% per month on the outstanding amount.
Support post project. To avoid extra unpaid work, it's wise to put in your contract that no further support will be given post the client accepting the final product, unless otherwise agreed in writing!
Ownership. It's a good idea to make things clear between you and your client about who owns what! In this case, your client will have complete ownership over the final product, however any usused concepts are still your property! I also include in my contract that any final work product can be included as part of my portfolio, and showcased on my website and instagram!
Terminating the contract. At any point for whatever reason, you or the client may want to terminate the contract early. This can be done, but just make sure you state in your contract your rights if this happens! For example, in the event that the client terminates the contract, the designer keeps the already paid half of the fee as a security deposit. This ensures your financial stability and encourages only serious enquiries from clients. In the event that you as the designer want to terminate the contract, you should refund the security deposit paid by the client.