What do I do on DI trade? I only know to do a 2HP 623OD

I always did (with 1 Stock): s.HP - 236MK - l.MK - 214MK (should be around 25% damage) and you get oki. You can also end this with level 1 or level 3. I would not recommend 623 OD, it's too expensive for the damage you get.