I have been using this IWISS IWS-2820M crimping tool to make up some JST XH2.5 Cables, it happens to be one of the cheaper crimping tools but performs better than a lot of the more expensive ones. Big Clive and The guy with the Swiss accent both recommend the same crimper. Video below.
You can get them on AliExpress for $A25 or so
You can get them on AliExpress for $A25 or so