There's no good way to do it, other than to not do it.

The strain on the header can be reduced by using some method of prying the cable slowly, like levering it from the mainboard, rather than just pulling on the connector (which tends to suddenly "let loose" causing an unwanted yank at one end..).

It's just the nature of the beast. That header was never intended to be touched beyond the factory. Bummer, eh.

-ml