Instead of taking and posting some likely poor quality photos, I looked for some decent vids on subjects similar to dealing with the mouse switches.
Each video has an incrementally little bit more useful info and comments to add. I think this is better than my posting pictures.
Note: during desoldering and soldering you have to be careful not to overheat the board and circuit pads. You can damage the board. It's a good idea to practice first...several times...on some scrap PCB board with similar devices on it that you've taken out of some junk electronic item. You do not need very high wattage soldering tools/settings to do this.
For personal, limited life items (like a mouse) you can also get away with not doing EVERYTHING to prepare a solder joint. For example you may not have to clean off all the old solder, and you probably
won't have to use additional flux. Often the flux in normal electrical "rosin" core solder will be more than sufficient to make an excellent connection. Also, with items you don't expect to last more than a few years you can likely get away with NOT cleaning off any flux residue. This is NOT ideal, but face it, we're not talking about a critical circuit here. Flux residue IS slightly corrosive...some electrical circuit fluxes more than others. Do not use plumbing flux under any conditions.
If you feel you must remove the flux residue after soldering things back together, find some 99% isopropyl alcohol. 91% is "ok" but you may need to provided added drying time for the extra water to evaporate. 70% "rubbing" alcohol is not recommended. A "good" pharmacy will carry the 99% stuff. Call ahead to verify. Or, you can buy "flux cleaner" at an unbelievably outrageous price at an electronics store. The flux cleaner and the alcohol are extremely flammable. BE CAREFUL re sparks, flames, and heat sources.
I never keep a full bottle near the work bench. I pour some into a very small sealable container and use that.
I recommend watching the last video just because it's a good overall demo. Pin-in-hole demo is at the 3:15 mark.
It shows what a skilled person can do.
Desolder and resolder a part
power jack (SIMILAR to what you find with a microswitch case tabs and signal leads)
This one uses a "solder sucker" tool (about $5-$10 at place like radio shack). Usually either a plunger type or a vacuum "bulb" type.
This vid uses a "plunger" type of solder sucker.
capacitor (this vid is kind of primitive, using primitive tools)
using copper braid
using a "solder sucker" tool with a vacuum pump (quite a bit more expensive)
Another "plunger" type solder sucker demo
GENERAL soldering "technical" discussion/demo
GENERAL soldering demos (surface mount, pin-in-hole, terminals, wire-to-wire)
I'm including this one mainly because it has EXCELLENT close-ups and shows some good techniques for various types of soldering