Very few things you need to do in DP:
On "my page" (top left button), then at the top right there is the Mission button.
Quest, 3rd tab for extermination battle (not active yet).
Raid button for bosses. Keep clicking it to refresh shared raid bosses. can get you a lot of rare bosses.
Also:
Gift + Gacha buttons, to get more cards and stuff
Ability Button, puts points into the top most abilities for more quest points, etc.
Enhance button for mission and to have stronger cards. Use the Limit Break tab first to raise R and higher cards immediately, then just feed normals into the highest rarity you have. Probably feed duplicate R's into their max LB'd card.
Don't think you need to mess with your deck/card layout because it automatically sets it up for you.