I agree with Hampshire carpenter. I always use decorators caulk as it is cheap, easy to clean off and you can caulk top of skirting as you go. Pinning with second fix nail gun is optional but helps to hold in til caulk goes off.

Hi

Screw and plugs will always be better, espescially if your walls are a bit bumpy...and the skirting needs pulling back. Most people stick it these days.

The best stuff I've used to stick it is yellow gripfill by evo stik...link
http://www.powertoolsdirect.com/evo-stik-gripfill-yellow-solvent-free-adhesive-350ml

It has an instant grab property, and It's water based so you can fill in the gaps between the top of the skirting and wall with it, smooth off with a damp rag...and paint when dry.

No more nails is similar (unibond), but a bit thicker in consistancy, so you have to push it back quite hard. It can be expensive because it's aimed at the DIY market...link http://www.vellumartwholesale.com/contents/en-uk/p596.html

Painters mate or decorators caulk is a flexible water based filler, but is excellent for sticking skirting on the walls, as it dries it shrinks, which pulls the skirting back...it also works with coving.

Try and buy solvent free, because it's easier to clean up... especially if you get it all over the wall :)

I'm sure loads of people will disagree but

I hope this helps

hi
if the walls are nice and straight after being plastered? carpenters will usually use grip fill or no more nails and just occasionally put a screw in to hold the skirting back tight until the grip fill/no more nails has set then remove the screw.

Use a product called Grip fill http://www.screwfix.com/p/gripfill-350ml/10261
,If your floor's are bare nail or screw some 2"x2" in 10cm lengh's along the skirting edge to hold the skirting against the wall if needed to keep a straight line until the grip fill has cured. Also recommended at skirting joins.If plugs and screws are necessary use car body filler to cover the pug holes ;)

I agree with hampshire carpenter
If You have the luxury of a 2nd fix nail gun then you can tack the mitres with this or you can buy mitre fix which holds the mitre perfect
If the walls have been plastered then make sure they are dry first otherwise they won't stick
Best regards

I always use clear silicone or no nails, clear silicone is cheaper.
Regards Trevor.