Depending on the situation, it may be a few hours or a couple of days that a turtle must remain in your care. Knowing a few basic things about initial care will keep you from getting into a panic about the situation and keep you from doing anything that might further injure or stress the turtle. You should know how to handle a turtle especially if you suspect it could be a Snapping Turtle. Snappers are very common to find on roads in many areas including the Texas Gulf Coast. Be extremely careful with any large turtle.
Large species are capable of inflicting serious bites.
They have very long necks that might be able to reach you if you pick one up by the sides of the shell. Someone with experience handling snappers can safely pick up smaller ones by their rear legs if there are no serious injuries near the rear of the carapace. Wild snappers will probably be more aggressive than captive raised ones. So keep this in mind if you've always handled captive raised ones. I suggest you use a broom or a long stick and push the turtle into a box.