Should I self manage (via online brokerages e.g SAXO, Cityindex) or should I appoint professionals to do it (via Syfe, StashAway, DBS digiPortfolio)?

Having some saving after deducted my monthly expenses (around 700-800). eg daily needs, insurance, bill, and existing RSP (S$200) with DBS. What can I do more? At what point that people go self manage and why go e.g Syfe? Already have 6 month saving from my current pay.