Ginn, I'm very fierce & very strict. Even my bro's gf & all my cousins very shocked at how strict I am (cos with my nephews & nieces, I'm super nice though still firm with them).
From 1yo, I use cane. But I only cane the palm & the sole of feet.
The first time we used cane:
My boy go near the fan when we already told him 'no, it's dangerous'. So my hubby sit beside the fan. My boy try his luck, his hand reach over to the fan, my hubby hit him with the cane. Try 2-3 times, he realised that we really mean 'no', he stopped. & from then, he nvr ever go near the fan again.
Usually we will give warning first (3 warning). 3 warnings we tell him very nicely that his action is not right, it's not nice or it's disturbing others. He continue trying to be funny, he will kena the cane. We used to keep a cane in the car too (during terrible twos stage).
Then we also hv notty corner (any flat plain wall can be the notty corner). If he's notty, he gets sent to the naughty corner. No moving, no fidgeting, no crying, no playing with fingers.
We've not used the cane for more than a year already. Once he realised that we mean what we say, taking away priviledges is more than enough to scare him (no toys, no TV, no playground time). Just hv to be firm initially so he knows that you mean business & he can't climb all over you.
My boy will try to manipulate us but once I get angry, he knows there's no turning back already. sure will get punished.
But now just need to tell him nicely & he will listen. That's why we are willing to try for #2 cos we realised that he's easier to manage now (no need to get angry all the time).
& thankfully, my parents don't interfere with us disciplining him. My mum is so proud that her grandson is so well-behaved when she brings him out with her friends. & she will tell me to continue to be strict so he won't grow up to be ill-disciplined. I see some of my nephew's behaviour, I feel very sad. Cos their parents too busy with work to teach them. & by the time the parents are home, they close 1 eye to everything cos only left that precious few hours a day to see them, they don't want to spend tt time disciplining them & getting upset. So it's a vicious cycle of bad behaviour.
btw, kids learnt fast. My boy picked up undesirable words from school. Immediately we told him cannot use that word cos it's not nice & explain what it means. Sometimes he will try his luck again. If he still uses the word after 3 warnings, notty corner & cane will come out. But so far, he stop after 1-2 warnings. Words like 'stupid', 'shit', 'idiot', etc. So parents must mind your language also. They really pick up super fast.