We may be motivated by the lecture content independent of any practical applications. Help motivate students by explaining the applicability of lecture topics both inside and outside of the course. Assume that students will have diverse interests and try to provide variation when motivating topics. Try starting class with an example of CS from current events.
Example: "This skill is needed to solve problems like..."
See this and related tips as a Tip Sheet: http://csteachingtips.org/tips-for-lecturing