This was discussed just yesterday.
smoke from passenger vent
The newer method is to use a vacum device, but you also need an air compressor. This is what the dealers are now supposed to use.
It is kind of neat. Vacum is used to suck the old stuff out. The empty cooling system is then under a vacum. That vacum is then used to suck the new stuff in.
UView Airlift is such a device, but you need the compressor to use it.