You can't. I've been in the same boat as you and there is no real work around. I ended up putting all of my sub-sessions within the description of the main session. It was a very manual processes. I put the suggestion to add this feature back (https://community.cvent.com/idea/subsessions). Maybe if CVENT gets enough complaints?
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Claire Johns
Director, Membership, Marketing and Communications
Society Of Cardiovascular Computed TomographyUnited States
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