well i was in Ranger battalion in the Army so no talking smack about my basic being easier, because no female can finish our basic, which is more than i can say for the marines basic.either way the marines are our brothers in arms and comrades and i fought with them in OEF and OIF so, that makes you my brother.
THE CONCEPT IS "LAW OF SPECIFICITY" MEANING:
to get good at something, the best thing to do is to do that exact thing over and over.basically, what we did was :15 weeks basic/4 weeks airborne school/8 weeks ranger/3 weeks layover. so i would know.
PULLUPS(same as below, switch grips/ elbow path)
CHINUPS (lat pull down, lat row)
PUSHUPS(dumbell bench press)
DIP(bench press w/ palms facing up as opposed to normal)
SITUP/(marine variation is hands across your chest, elbow touches knees)(plank or bridge, side bridge, hanging knee raise, flutter kicks, scissor kicks)
3 MILE RUN(sprints,4,5 mile run, front squat,bulgarian split squat, and lunges)
We did the capitalized ones for hours when we were punished.
i suggest you focus completely on these capitalized ones and the ones in apostrophes are exercises that help dramatically.one other thing is to do workouts that involve body weight and focus on HIGH rep ranges because you will do these for hours, it doesnt end in the PT field. they will eff with you all day and sometimes wake you up in the middle of the night to do whatever they feel like, such as pushups. look up the descriptions in www.menshealth.com
good luck Marine