Just started working, how much of my RM3000 salary should go to savings?

Realistically, since you're staying with parents, this is the best time in your life to save hard, before car loan, rent and family expenses arrive. I'd aim for at least RM700-900 a month if you can. Order of priority from my experience: first build an emergency fund (3-6 months of expenses), then start investing small and regularly, ASB, EPF voluntary top-up (good returns plus tax relief), or a simple index fund. Automate the transfer on payday so you don't 'accidentally' spend it. You don't need to live like a hermit, budget a reasonable amount for makan and fun so you actually stick to it. The habit matters more than the amount at this stage. Also avoid lifestyle creep and easy credit; that's what traps most fresh grads. Consider chatting with a licensed financial planner once you have more to invest.

From my experience starting out, a good target is to save at least 20 percent, so around RM600 from your RM3000, but since you stay with parents (low cost), you can push higher, maybe 30 percent. The classic guide is 50/30/20: 50 needs, 30 wants, 20 savings, but living at home you can flip more into savings. First, build an emergency fund of 3-6 months expenses in a separate account, that's priority one. After that, start something like ASB or a low-cost fund, or even voluntary EPF top-up which gives decent returns and tax relief. Automate it, transfer to savings the day salary comes in, before you spend. Living at home now is your golden window, save aggressively before rent and family costs hit later. Don't live like a hermit though, budget some fun so you sustain it.