Obviously the following isn't legal advise, just examples from contracts I have worked on over the years. I have no way of knowing if these clauses are valid where you live/work (though they have appeared in pretty much every international contract I have worked on. As always consult a local lawyer.
Here is a section to go at the start of your contract, in order to define the parties and the start date of the contract. This will address the first point I made in my post above about identifying the parties to the agreement. If you are an individual "trading as" then adjust the part about company registered number etc.
THIS AGREEMENT is made on the [day] day of [month] [year] (the "Effective Date").
BETWEEN
(1) [name of Photographer/Company] a company registered in [Insert country/state of registration] under registered number [Insert registration number] whose principal place of business is at [Insert full address of principal trading location] (the "Photographer"); and
(2) [name of client] a of [Insert full address of client] (the "Client").
This is a jurisdiction clause but please note it is from a UK contract so it mentions the Contracts (Rights of Third Parties) Act 1999. If you aren't in the UK you will need to delete that and obviously change the law that will govern the agreement and the courts that have jurisdiction.
11.10 Law, Jurisdiction and Third Party Rights. This Agreement shall be governed by and construed in accordance with English law and the parties submit to the exclusive jurisdiction of the English courts. No term of this Agreement is enforceable pursuant to the Contracts (Rights of Third Parties) Act 1999 by any person who is not a party to it.
and a severability clause....
11.8 Severability. If any provision of this Agreement is held to be invalid or unenforceable, in whole or in part, that provision or part shall to that extent be deemed not to form part of this Agreement. However, the validity and enforceability of the remainder of this Agreement shall not be affected.
As mentioned by a previous poster please note that it is not described as a contract between two parties but an Agreement between two parties. Not being a lawyer I have no idea why that is, I just know that every contract I worked on over the last 20 years was worded that way.