Starting a project for a client without a spec sheet is the easiest way to burn yourself, as a freelancer. A spec sheet will give both you, and the client, a clear and complete idea of what you need to do in fulfillment of the contract. It will also increase the chances of you getting paid substantially.
The formatting is up to you. You can keep it electronic and modify it per-client, or you can make a generic copy with room for writing and fill in details on the spot. But whatever you do, I recommend you have the following key fields covered:
You need to have a clear idea of what the client is hoping to gain from you. In most cases, this is simply a presence on the internet, increased visibility, and other benefits. Don’t promise things you can’t deliver.
This is a handy reference for your work, and should play a big role in your design. If your clients’ clients are elderly, consider large type and simple navigation; if your target is more youthful, you can feel free to take the easy road and use grunge.
Scope of Work
State, in no uncertain terms, exactly what you are going to do. It might also be a good idea to substitute instead deliverables, which will be more specific. Remember, be detailed.
State, item-by-item, the costs for design (web and graphic), development, copy writing, photography, installation, and SEO. I prefer to present this as a checklist, so that a) I remember everything, and b) the client can see all the options.
If you charge by the hour/word/photo, you may make the cost estimated instead of final. I prefer to have a column for a time estimate, and a final amount charged based on this, for reasons I’ve detailed in the past.
A due date is all well and good, but it’s even better if you can provide specific, realistic milestones for certain aspects of project completion. You’ll be able to pace yourself better, and your clients will have a very specific idea of how long things will take, and if it would be reasonable to contact you now with changes to the copy.
You do collect payment up front, right? It will be much easier to ask with an official-looking contract, believe me. Include an area with room for several payment milestones, even if you only intend on half up-front and half on delivery. Who knows, your client might feel more comfortable paying in bite-sized installments as the project is completed.
Terms and Conditions
You may include this as part of a spec sheet, or as part of a separate contract, but definitely have it. It probably won’t come up, but you should definitely, definitely (definitely) have it. A lawyer-reviewed version is best, but if your friends aren’t done law school yet you might look on the interwebs for some terms.
In my spec sheet/contract, I include a summary of each section of my terms and conditions in bold as the first sentence. It saves time in reviewing them.
My own spec sheet is a modification of the excellent template provided by Shane & Peter here, which also contains more insight on this stuff. If you are looking to create your own, it’s a really good place to start.