TheReelChuckFletcher
Former TheRillestPaulFenton; Harverd Alum
You offer-sheet first THEN figure out the cap (sending out Skjei/Turbo) after. You definitely don't trade before OS because if it's not signed or signed-matched, now it failed AND you've traded away a player you must replace.
Unless you know that a team can't match an offer sheet. In that scenario, you do want to make the cap room first. Again, I think both the Oilers and Rangers are incredibly vulnerable.