Some good advice already, so to summarise :
“Windshear x 3” warning (reactive / immediate warning) : do the WS escape manoeuvre - do not change flap under any circumstances until clear of WS and then perform a normal G/A.
“Go-around, WS ahead” or “monitor radar display” : ideally a normal GA and turn to avoid (flap 15). However if you encounter actual wind shear then do WS escape.
If you ‘pilot detect’ actual WS (conditions listed in QRH) do the WS escape manoeuvre.
For me the grey area comes if you get positive shear first - that’s what happened to me once - the thrust levers were coming back and speed going up so I actually called “unstable go-around” and did a normal go-around. During that got the negative WS and reactive WS warning so converted into WS escape. The point is if you’re not sure and you’re not receiving a reactive warning then a normal go-around is a good option - pressing TOGA and getting the aircraft climbing away at 2000ft/min is a pretty good starting point. And if you’re doing that you’re not in negative WS!