I know I should have an Electrician do this but it seems so simple. I want to move my light switch to the other side of the wall. Can I get the same wire they used and connect it to the existing wire to make it longer and snake it through the wall to where I want it?
Also I have 1 outlet box but I need 1 more not to far from the 1 I have. What can I do?
(other than call an electrician)
Thanks

These are fairly simple projects well with in DIY. Shut the breaker off. Note whether it is a 15 or 20 amp. Most lighting circuits use a 15 amp breaker and 14-2 with ground. If it is a 20 amp breaker, all the wire connected to it must be the larger 12 gauge. Your ploy of buying wire just like the old is a good one. And you are correct about covering the old box with a plate. You must leave access to the splices. You could even consider running a 3 conductor cable and wiring it up as 3 way switches. Hardest part may be snaking the wires. Connect all the blacks together and to the brass screw of the switch. White to white and to the plated screw. Bare to bare and to the green screw. Adding outlets will be about the same. If they are on a 20 amp circuit, again, you must use 12 gauge wire.

Look for ''old work'' boxes. You just cut a hole in the drywall to fit and tighten up a screw to clamp the box to the drywall. It is a pain to try and nail boxes to the studs after the drywall is on.

If tkrussel adds any details, heed them. I carefully leave the harder questions to him. I answered mainly to assure you it was something you could do with a little help from here.

If when you say "connect it to the existing wire to make it longer ", that you want to just splice the new cable onto the existing, sure, as long as the splices are in a junction box, with the proper cover for that box, AND the box is accessible. This can be either up in the attic, or down in the basement.

If neither are possible, the you will need to mount the box in the finished wall, and have a finish blank plate exposed on the surface of the drywall.

In other words, do not bury any splices behind finished surfaces.

To add another outlet, you can install a new cable from an exisitng outlet box, to the new outlet box, again either fishing up into the attic and down to the new outlet, or vice versa through the basement.

If neither are possible, many times wood baseboad can be taken off, a channel be gouge in the drywall, lay the cable in the channel, and re-install the baseboard, being very careful not to drive any nails through the cable.