You can really prune anywhere - the branches will re-sprout buds somewhere near the ends where you made the cuts. Don't be afraid to prune back hard. You can cut back past all leaf growth and it will be fine. If you don't cut back hard enough and only trim the tips, you will actually compound the drooping problem by increasing the weight at the branch ends with more branchlets and leaves.
Like Rick mentioned, a hard prune now and then smaller "maintenance" trimming later (next year and on) will increase the overall branch strength and structure and give you the shape you seem to be wanting.