Cargo pants - the kind with pockets on the thighs - are good for concealment. And you can balance out any lumps by putting your phone, pocket knife, or other items on the other side.
Some employers frown on that kind of pants, but there are some “yuppie” style cargos that may avoid the “too casual” category. Extra “hammer loops” or unwanted frills can sometimes be removed by careful razor blade work.
Dark colors will hide lumps or ridges better than light colors; there’s less visual detail for the eye to pick up on. Most cargos come in tan or light brown, but you can occasionally find darker ones, or dye some yourself. There are web sites on how to do it, but it basically comes down to buying the dye on eBay or Amazon, a plastic bucket, and some long dishwashing gloves so you don’t dye your arms along with your new pants. You want a “color-fast” (fast as in “permanent”) dye, and make sure to wash the pants a couple of times before wearing them to avoid any “new blue jeans” effect.
You can help “guide the eye” by wearing a patterned or bright-colored shirt or necktie; most people focus on what stands out. Don’t overdo it; you’re after “nice”, not “1970s used car salesman.” If most people wear short sleeves, wear long sleeves, or vise versa. You can keep well within accepted boundaries while still being different enough to direct their attention. Flip side, overly-dramatic upper clothing, piercings, tattoos, or hairstyles will direct some people’s eyes away, and down, particularly if they’re pushing the limits for where you are.
Oh, and you should wear shoes that are both plain and similar to what others in your area or business wear; men tend to focus on the top half of the body, but women will sweep all the way down when checking someone out; you don’t want anything that will cause their eye to linger.
Also, if you wear similar pants and shoes - they don’t have to be exactly the same, just similar - every day, people’s eyes slide over them because they’ve already checked you out and didn’t see anything. “The eye avoids the ordinary.”
And finally, most people are so wrapped up in their own head, you could drop your pants and waddle around with your tool strapped to your knee and half of them still wouldn’t notice. And the ones who *do* notice would probably get distracted by something else before they said anything, and then would forget it completely a few minutes later. And if someone *does* bring it up, you can then choose between “wut?”, “trouser snake!”, or “is my colostomy bag leaking again?”
