The following directions are based on the idea that you are replacing existing doorknob/lock hardware. If you are using a new door and must cut holes for the knob and lock set, refer to the installation instructions that came with your new hardware for specific advice and a template for cutting.
Begin by removing the old doorknob and lock. These are generally secured by a number of Phillips head screws that vary in length. Remove screws on the inside of the deadbolt. These are very long and once they are out the deadbolt may literally fall to the floor in pieces. Be careful to save all the pieces in case there is a problem. Then you can reinstall the old lock.
Once the lock mechanism is out you can remove the deadbolt. If your new hardware is from the same manufacturer of the old hardware, it is possible that you can leave the old deadbolt in. Consult the directions to see if it is compatible with the new hardware. Insert and secure the new lock mechanism. Tighten the screws and test the lock using the key provided. It should turn easily. If there is difficulty, make sure you've properly aligned it. Be sure that the screws are facing into your house so they cannot be removed from the outside.
Your old "strikes" or "strike-plates" are also probably compatible with the new hardware. However, there have been security advances in lock design in manufacturer in recent years, so go ahead and use the new ones.
Remove the screws from the doorknob. Generally it is difficult to get a screwgun into the head of the screw behind the knob, so use a screwdriver carefully. It is easy to strip the heads on these screws. The doorknob will come apart easily once the screws are removed.
If you can, and want to, use the old latch mechanism. If you want to install the new one, slide it into the existing hole and secure it in place with the screws. Then insert the new knob and secure it with the screws. Again, be sure that the screws are facing into your house so they cannot be removed from the outside. Open and close the door several times to make sure all the mechanisms are in proper working order.
To install the doorknocker use the template provided with the product. Make sure that the template is level when you line it up. You should also check to see that the door is level. If you door is not level and the template is, the knocker will appear to be crooked even though it is level.
Be sure to compare the product to the template, it is not unheard of for the wrong template to be sent in a package. If the holes are off by even a small amount, you may need a new door. If the door is slightly off level, it is better to line up the knocker so that it appears to be correctly oriented on the door. Once you are satisfied that the template is straight, strike the hole marks so you can begin drilling. Remove the template and drill the holes. Be sure to drill a level and straight hole through the door. It is easy to get "off line", especially with hollow core doors. Check to see that the knocker will fit into the holes and then attach it with the provided screws.
* A side note here. If you have a steel door, there are magnetic doorknockers that are available. They are generally well secured and offer the versatility of no drilling and easy removal.
As with the knocker, check to make sure that the kickplate is level, it too can look crooked if it is level, but the door is not. If the door is slightly off level, it is better to line up the kickplate so that it appears to be correctly oriented on the door. Use duct tape to hold the kickplate in place while you drill pilot holes for all the screws needed to attach the kickplate. Once the holes are drilled, secure the screws and then remove the protective plastic film from the kickplate.
Installing the house numbers will require the removal of the old numbers and the drilling of pilot holes, whether into wood, concrete, or brick. If you are attaching the numbers to a brick facade, it is easier to drill into the mortar than the brick. For brick and concrete, you will need to use a masonry bit for drilling. Once the pilot holes are drilled, secure the numbers with the screws provided.