Just experiment. I swim, bike, run, and lift 3x each every week with 1 rest day.

My favorite rotation is to swim/bike on days 1/3/5 and lift/run on days 2/4/6. On day 2 I lift weighs (chest, shoulders, legs) in the morning and run in the afternoon. On day 4 I reverse it (back, core, and arms). Day 6 timing is flexible because it's the weekend and my exercises aren't heavy (body weight exercises only), so they don't affect my long run much.