when should I start my toddler to teach how to swim

i would say now take him to the swimming so he gets used to the water.ask your locel swimming club their advice

I'm not good swimmer also, my husband and I introduced swimming to my daughter when she was just a couple of months old (under supervisor though). So, you can just begin as early as you want. If you can't swim, just take the un-deep water and have fun playing water with him. Take a swim lesson together, that will be more good, not only for yourself but also for your son.