For generations, English speakers used he, him and his as the unnamed agent in written examples.

No longer. We strive for gender neutrality.

Please don’t strive too hard.

He? or She? Pick one.

Do not shy away from using he when it helps you  make your point.  That said, do not shy away from using she, if that helps you make your point.

(I once worked for a company that gave conferences for nurses, at which 98% of registrants were women. Yet when I drafted instructions such as Hand the registrant her name badge … my boss would correct it to Hand the registrant his name badge... because he was “standard.” I would sigh, and then change it back to she.)

When I write instructions that apply to either men or women, I alternate between he and she.  I use he when giving an example, and then—being clear that I am giving another example—I use she.

What about using both, together?

You can, but it’s a sure fire way to annoy your reader, to say nothing of too much work on your part. Consider the inanity of these phrases:

After lunch, he or she can visit the spa. He or she might opt for a massage or he or she might prefer a soak in the hot tub.

Ask him or her if he or she would like an upgrade.

My advice has always been:  Don’t make your reader work hard. By using a string of he and shes, you risk frustrating or sidetracking your reader.  Not to mention, you’re telling your reader you think he is too dumb to figure out that the situation applies to both sexes. (Who thinks that last sentence only applies to men, just because I used he?)

S/he? Horrors!

Abomination! S/he shrieks “I’m now being gender neutral!” and completely disrupts the flow of the sentence. Use it only when your goal is to be conspicuous for the PC-ness of your writing, and when you are not concerned that your reader grasp anything else you might be saying.

Use names.

There are plenty of gender-neutral names you can assign to your faceless, sexless examples: Chris, Jamie, Mallory, Casey, Alex, Jordan, Quinn and more.  (Granted, these are English names—if you want to encompass multiple cultures in your examples, you can’t take this route.) Using names works well if you are giving one or two short examples.

While you don’t want your reader to work too hard to grasp your meaning,  remember that your reader is smart enough to discern when he refers also to she, or vice versa.