There are only a few things to know that can insure your ukulele will last a long time and continue to sound and play well. Laminated instruments take a bit of care, but solid wood instruments require more concern, even under “normal circumstances”. First lets go over Things that all ukuleles require.
1. Normal temperatures. Treat your ukulele like a person, or at least a pet. Don’t talk to your ukulele. Unless you really need to.., But consider that when wondering what is an acceptable temperature for your ukulele.
So no hot or cold cars for much more than you would like to experience. Cracking/warping/glues loosening etc. can occur.
2. New strings at least once a year. Twice a year or more if you can. Even if they don’t break they get inconsistencies in the radius. Intonation, or the accuracy of the pitch as you go up the fretboard, will usually go off on at least one of the strings. It is not always a visible dent in the string, but there is a precision with a rectified new string that gives a clearer more accuratte tone.(koolau,aquila…). Be aware that strings stretch out so you may go out of tune for a while, this also depends on how much you stretch them out. Here’s a full How To Video/Tutorial on How To Change Ukulele Strings
Ukulele Cleaners(not a necessity): Do not use furniture polish or just any wax on your ukulele. It may not be a problem, but it can be. If you don’t want to buy another cleaner just for your ukulele, then use a very lightly dampened rag wrung out and wipe dry. A common favorite for cleaning minor stuff is the Dunlop 65 guitar polish and a micro fiber cloth. If you want to find something at wal-mart or maybe your hardware store that will really gloss up yout finish try the Turtle Wax Premium Grade Rubbing Compound (says clear-coat safe). This will be fine on any gloss Asian import but I would not use it on a higher end uke or local maker. There are a number of guitar polishes you can use. (feel free to share your experiences in the comments)