In your SafeCracker tag, ENTRY_ID
will be replaced with the actual entry ID of the new entry. So just use return="sthome/blending/ENTRY_ID
. This will redirect you to sthome/blending/45 (for example).
Then, use entry_id="{segment_3}"
in your sthome/blending template - though if you're using a standard Channel Entries or Safecracker tag on that page, it should read the entry ID automatically (since its the third segment).