As your child gets older his naps will change, over a period of time you will be cutting out the morning nap. An indication that your child no longer needs a morning nap is a) is harder to settle for the nap or b) is harder to settle for the lunch time nap.
Your child will need a lunchtime nap of some sort probably until he is about 2.5/3. A sign that he is getting to much sleep during the day would be that he is harder to settle at night or wakening earlier in the morning. You should always monitor your child over a 3 day period to get a true picture and rule out teething etc.
So, if you find your child is consistently harder to put to sleep at night then you should reduce his daytime nap. You do this gradually by reducing it by 10/15 minutes (depending on how long the nap is) every 3/4 days until you have resolved the problem. Now you do need to be realistic, if your child is 1 and you have been shortening the naps every 3 / 4 days so that he is getting less that 1 hour of a nap and you still do not see a result then there is something else wrong.
You should always reduce the nap rather than push out the bedtime while your child is having naps.
Now you may feel by reading this that your child is similar to a robot! As I read it back to myself it sort of sounds like that, sorry! Your child is not a robot and you will have days where everything goes to pot! You will have days where you can’t stay at home or it is just not possible that your child sleeps at certain times etc. Don’t panic, that is absolutely fine, if you have established a good routine that works for you, be it what I have suggested or not, and you need to go out or do something else, don’t worry, once it is in place you can go and do things. However your child may be a bit fussy that day, but you will know why and the next day get back to the routine. If you have your routine in place 5/6 out of 7 days then you are doing fine.