Assuming you're lecturing at a university, many institutions now have a "centre for teaching and learning" or similar office ("teaching innovation", etc.) where lecturers can receive support and feedback on lecturing skills and course design (among other things). Not all CTLs are well promoted on their campuses, so you may need to ask around.

Re: some of the other commenters' suggestions, you might want to research the "flipped classroom", which is the popular term for the model they're discussing (students read materials pre-lecture, and lecture time is re-purposed for discussion and engagement activities).