Strength Training Breathing Quick Tips :
For Squat: Hold breath on walk out, breath out and take a deeper breath and squat. Repeat taking breaths for each 1-3 reps depending on conditioning levels.
For Bench Press: Hold breath from start to finish 3reps at a time before re-catching your breath.
For Deadlifts: whatever is comfortable, Bob People's used to deadlift with all his air exhaled. For me I like to scream out all my hair and quickly huff it back in when I pull.