When speaking about the best quality translations possible, the most important thing is choosing the right translation company. Should you want to write the source copy yourself, in order to reduce your costs, there are some steps you must take in order to make sure your copy is translation-friendly and that the final foreign language version of your text will reach your standards.
The first thing you must do is to ensure that the source text is carefully proof-read before you submit it to a translation company for a quote. They cannot make a good translation out of such a source text, and if they do, the company will most certainly charge you more for the extra work they have put in! If a text does not make any sense in the source language, then almost surely it won't make sense in the target language either. The only option you have is to be clear, concise and be sure the text states exactly what you intended it to say!
Should you want to translate large technical manuals or lists of trade-specific words or phrases, it would be a good idea to provide glossaries or background reference material helps to make sure that your translation is written using the same terminology as used in previous documents. You see, consistency is always a thing to keep in mind!
Should you want the translated text to have a particular tone or style, you must make this clear when you commission your translation. If the translators have all the information about your target readership and intended message, the style you wish the text to have will be more likely to be achieved. So, when writing the source copy of any kind of text, you must think about all these issues. Otherwise, any changes you want done later will affect the price you will be charged with. Not to speak about the extra time it will take to redo the project! For instance, if your marketing department took a couple of weeks to develop a catchy five-word slogan, the translator will need time to find something that works equally well in the target language.
So, no matter what your translation needs may be, feel free to ask any professional translation provider about how the whole process really works. This is the best way to prepare yourself for the situations when you will have little time and energy to look into the translation business!