You can use a tiny bit of saline, without additives/preservatives, to help get as much sperm as possible into the syringe, but you don't need to worry too much about leaving a little behind. You'll probably have better luck getting the semen out of a cup since you could suck the baggy or condom up to the syringe and block the opening, but you may get a larger sample with the baggy or the special collection condom. There are special collection condoms for this purpose that do not have sperm-killing chemicals. Do NOT use a regular condom because it may contain chemicals that kill sperm.
Take a clean or sterile glass or plastic cup, baggy, or collection condom and have the male ejaculate into it.
