Data transfer

Don’t think there is a “best” way, depending on what you have and which model involved.

1. WiFi, share the source and copy into destination. Nothing required but much patience.
2. Ethernet, simply share and transfer, only need a single network cable. May take a while.
3. If you have the right connector and cable - FireWire or Thunderbolt, put the source computer into target mode (press and hold T after restart), connects to destination computer and copy.
4. If the source is older model with removable storage device, and you also happen to have suitable external enclosure, take it out and put into enclosure and plug into the destination computer.

If you are asking about transferring user profile to new laptop, follow below.

Move your content to a new Mac – Apple Support (AU)

if you use Ethernet, you can often have more trouble-free results by using two cables, both connected to Your Router.

If you use a Thunderbolt device to device transfer (as opposed the Target disk Mode) you may need to plug in the cable and then use

System preferences > Network ...

and Add [+} a new device that will appear there to the list of devices for networking with a name that suggests ThunderBolt-to-ThunderBolt transfer.