There are lots of resources out there for web designers; just do a web search and you'll find all manner of tools and guidance to help get your website up, running and looking professional.
One area that many webmasters forget or don't realise that they need to be aware of is the standard of their written content in terms of language, punctuation and grammar.
Many web sites are sales oriented and so the standard of written content becomes crucial to the success of the sales pitch. Getting writing advice is easy on the internet.
Firstly, you'll need to structure and draft your sales pitch. Make an outline of the main areas you want to cover and the points you feel you need to make. Draft each area in turn and make sure they fit together as a cohesive pitch. There are many places to get advice on how to structure and write sales proposals. This article doesn't focus on sales pitches but on ensuring that the quality of writing reflects well on you and your business.
Once you have drafted your sales pitch, remember to check it thoroughly. Leave it to the side and do something else, for at least 2 to 3 hours, preferably a day or two. If you try to check it too soon after drafting it, you will not find the errors that will undoubtedly be there. There are many websites out there that give in-depth advice on how to do this, like
http://www.freewritingadvice.com (
http://www.freewritingadvice.com/indexfiles/editrev.htm).
For sales websites especially, you should ensure that your spelling is perfect. Spelling mistakes look unprofessional and if your web page looks unprofessional, why would someone pay you for a product or service which may turn out to be equally unprofessional? True or not, that's the perception you will be giving.
Look closely at the language you have used. Is it ambiguous? Could it be interpreted in more than one way? Is it misleading? If so, reword it. If you can remove the need for a potential customer to need to clarify a point, you stand a better chance of making a sale right away.
Look for areas where you could be more concise and where redundant words could be removed. This makes your text more readable and reduces the readers' ability to misinterpret what you've written. This will also cut down on after sales queries as the customer should be clear about what they are buying in the first place.
Make sure that any facts you are relying upon are correct. Remember that information gained from websites is not always reliable. Since the internet is largely unregulated, it pays to cross-check, or corroborate facts, in more than one place before using them for your website.
Don't fall into the trap of publishing your web content without checking it. While there are positive advantages to being able to publish quickly to the web, the disadvantages of putting badly written web pages in front of potential customers far outweighs them.