- Use the trademarked name as a name. That means it's capitalized and NOT used in place of a common noun (such as tissue). And include the word "brand" in the description: (Kleenex® brand tissue). Note that while the trademark symbol isn't required here (since you're being pretty clear that the brand is a brand) it can be safer to add the symbol anyway just so there's absolutely no confusion. This keeps the company happy and gives the writer added protection.
More examples (without the symbol, but showing brands as names along with common nouns):