I do a lot of HDR bracketing with my K-70. Once you've figured out how to do it, such as suggested by @
cdw2000, plus any other relevant settings such WB, ISO, F-stop, I would suggest you then save these settings under one of User 1, 2 or 3 dials, and rename it to that of your choosing. You can then instantly bring up these settings when you want to shoot bracketing. You can also make changes to the setup whilst shooting, such the number of bracketed shots or the EV value between shots. If you go to another camera setting, such as AV or Manual, and then back to the User mode, without having switched off the camera, those last changes will still be reflected. If you switch off the camera and then return to using a User setting, it will default to your original saved settings. By using this feature, you won't forget any important settings that you might later regret after the shoot!