Tool for tightening an anchor bolt
Use a deep well socket and ratcheting set.  Given that this is a 10mm nut, you don't want too much torque.  Assuming you don't crush the surface you are tightening to and have a sufficient washer, you need to be concerned with torquing the bolt off.  In certain cases, I've taken a 1inch diameter by 1.5ft lead pipe and put it on the end to get extra torque, but I advise against this if you don't have a feel for how much torque you are applying.  You can find small scale torque wrenches, but if you are going to do so, I suggest you look up the recommended torques to apply to the bolt you are using (you need to know what type of bolt it is).