I think it's okay to make regular purchases every month, rather than just buying all at once with all your money,
The DCA method or all in method has its own advantages and disadvantages.
but the dca method can be said to be safer.
Continuing to use unused funds is the most important thing to avoid sudden needs and not disrupt investments that have been made. What you do in purchasing is, of course, adjusted to the funds you have at hand; don't force yourself to use funds from other places. Purchases can use any scheme that is considered very good, and DCA is of course highly recommended for use; it is clearly easier to do and very safe. Once again, every investment is always adjusted to the market situation and proper analysis before deciding to buy so that you can get a decent price and can provide hefty profits later.