How to fill a gap between drywall and ceiling Step 1: Mesh drywall tape. Start by placing a strip of fiberglass mesh drywall tape over the gap so that the top edge of the tape is flush against the ceiling. Step 2: Apply joint compound. ... Step 3: Paper tape. ... Step 4: More mud. ... Step 5: Let the mud dry. ... Step 6: Sand. ... Step 7: Paint. Sep 25, 2019