It's very easy.
For your Spark page, just click on the "person" icon, under the "Sharing" column header, in your page name row (in My Spark Pages), and choose the team you want to share it with. As for sources, do the exact same thing - go to your Integrations page and select the "person" icon next to the source you want to share, and choose the team you want to share it with.
Sharing your sources with other team members gives them access to your assets, helping them improve their results when searching for the best content to give to a prospect. As well as sharing your pages with other team members helps them discover why you are so successful. Don't forget to have them share their sources and pages with you!!!
Video: How to share a content source with a Team
Video: How to share a Page with a Team