Before answering your question, we would like you to accept our appreciation for resorting to a safe sexual practice. Great. You are already a champ. To answer you, don't ever flush the condoms down your toilet. It may be quite tempting to do that. But it is a bad idea which might backfire. Over a period of time, condoms may add to the blockage and toilet overflows requiring you to seek professional assistance and who will find out condoms are the main reason for the blockage. It may then become too embarrassing.
Remember, latex is bio degradable and will not disappear magically when flushed. It may go down the drain, it may not block your toilet, but it might block your septic tank leading to loads of unpleasantness later. What might seem a good idea for a while, might make you resent later. So, don't flush your used condom down the toilet drain.
Don't throw the condom in the living room trash, as there is always a possibility for your domestic help or your other family members to notice it. If you have pet in your home, then there is always a possibility that pet can dig that out and stew it outside the trash to make things very embarrassing for you. Remember, pets have heightened sense of smell and it is not difficult for them to identity a condom in the living room, even if your used condom gets settled at the bottom most portion of the trash.
Needless to say, don't throw it on your kitchen trash or on your sunshade. It may be very tempting to throw it on the sunshade by opening your bedroom window. But it is always not a good idea.
Safe disposal method
After carefully withdrawing condom after ejaculation, hold it from the top and tie it to ensure semen is trapped inside the condom completely. Then wrap it over a larger sheet of paper and throw it in the trash that nobody notices immediately. Then you can throw that thrash in an open area next morning while you travel to work.