MAN- Cover 0 man d ( with no zones at all), have the CBs playing BNR and the safeties will be at unequal depths as they will be maned up. IN cover 1 the corners will be up on the WR and playing BNR and one saftey will be deep to play one deep zone, in 2 man under the corners will play BNR and be up close with both safties at equal depths to paly two deep zones. Now usually when playing people the only time a cover 0 defense will be used is in a blitzing situation. i only use Cover 0 to try and BNR the WR long enough to get a sack, if they get beat in a=man coverage you could give up a TD if you dont get to the QB.
Slanst inside kill man as well as the c- route out of WR corners in gun split offset (its in other plays too but this is the one i use cuz you have a man beater on the left and a zone buster on the right with the flat, corner and streak combo). On the c- route use a bullet pass with pass lead in when the wr makes his first cut inside, DO NOT TRY against LBs in yellow zones.
Cover 2- Both safties will be at equal depths to split the field and the CBs will play BNR in flat zones. The sidelines are usually vulnerable in these coverages, with that said some 3-4 variaitons and the nickel 355 variation have LBs in purple zones so the middle wil be more open, ALWAYS pay attention to what the LBs are doing because they are usually the players that leave some area of the field vacated and that is where you want to attack.
COVER 3 - One safety deep, One safety will rotate in, the cbs will not be in BNR and will play off the WR and will back up immediatly at the snap of the ball Quick passes to fades and slants out can be used to hurt cover 3 and 4 coverages. Another thing is that the LB is usually the one coming in to cover the flat so if you have a quick HB you can pass to them in the flat and the LB usually wont be quick enough to get there and you can get some nice yards. Sidelines are open as well if not purple zones are being used.
COVER 4- Both Safeties deep, CB play off of WR and back uphave immedialy at snap. Middle of field is usualy the weak spot since cover 4s purple zone. Cover 4 also usually doesnt have coverage in the flats which can be exploited. This is a defense usually played to prevent deep passes and probably wont be used much outside of long downs (i.e. 3 and 20 or 4th and 15) or at the end of a game or half. Cover 3 and 4 Defenses are easily exploited with quick passes to sidelines (Moitioned wheel routes, quick slants out, and fades)
I hope some of this helps you, but remember you might be reading the right defense but the wrong variation. Always check to see where the LBs are going cuz that might determine what part of the field is open. If anyone has PS3 and is serious about madden and has some stuff to share Im up for some labbing, I have some nice defensive and offensive schemes and am very open to sharing with someone to try and improve my game. Hit me up PSN wandeezy623