Always use as an adjective. Trademarks and service marks are adjectives. Not nouns or verbs. Therefore, a mark should always be used as a modifier (e.g. Champion® Toilet, Speed Connect® Faucet, EverClean® Surface).
Identify consistently. When citing a trademark or service mark, it is not necessary to use the mark in every occurrence. Generally, use a trademark or service mark upon first reference on each page of a document or web page.
Do not use as a plural or possessive. As an adjective marks should not be used as a plural or possessive, unless the mark itself is plural or possessive. ( e.g. Champion not Champion's or Champions, Speed Connect not Speed Connect's or Speed Connects, EverClean not EverClean's or EverCleans).