Caring for a straight razor involves a bit more attention than holding it under a running tap then chucking it in the bathroom cabinet. This course of action might be OK for a disposable razor as by definition the blades get thrown away so it doesn’t matter. A straight razor has just one blade, it’s delicate and doesn’t respond well to harsh treatment, but treat it with respect and you will never need to buy another!
First let’s cover some do’s and don’ts.
Rinse your razor thoroughly after use, taking care to remove all trace of soap.
Allow it to dry before storing it away in its box. Dry between the scales as well as the blade itself.
Put it out of reach of children! This might seem obvious but kids seem to love these things.
Always treat it with the respect you’d show anything that’s very sharp.
Use a razor oil such as Jenkin's Razor Oil to protect the razor between uses.
Knock the edge of the blade on the sink if rinsing - it can chip or break!
Use it as a box cutter/letter opener/pencil sharpener - you will ruin it!
Leave it lying around open when lathering your face etc. - your fingers will regret it!
Ever, ever, EVER use it to behead a pimple or lance a boil - the results can be truly horrible.
Use it for any purpose than the one it’s made for.
If you are not going to use your razor for some time then carefully applying some petroleum jelly (such as Vaseline) will help protect it from rust. Otherwise, apart making sure your straight razor is clean and dry after use, there are only two tasks that you’re ever likely to perform. These are stropping (frequent) and honing (infrequent).