FEW things in life are perfect, but if you’re working with wood and want it to look unblemished, there are things you can do to make it so. The easiest of these is patching up problems with wood filler.

Wood filler dries quickly, which is handy when you’re in a hurry but makes getting it off your fingers a pain, so wash it off straight away or wear disposable gloves. You can usually sand wood filler quite quickly after applying it, but should leave deep repairs overnight to harden.

If the filler hasn’t hardened properly before you sand it, you won’t get a good finish, so don’t continue if it seems soft. You may need to start sanding with coarse sandpaper, such as 40 or 60 grit, and work through to finer sandpaper, such as 80 or 120 grit. Wipe the repair with a damp cloth and allow to dry before painting.

For repairs on things where movement occurs – such as window and door frames – use flexible wood filler.

Unlike most flexible fillers, this isn’t rubbery in texture and can be sanded in the normal way.

Some wood fillers can be applied straight from the tub or tube, while others have to be mixed before use. These comprise the filler and a small tube of hardener, which you mix together when you’re ready to fill – following the manufacturer’s instructions. The problem with these is that getting the quantities right can be tricky and the filler can harden too quickly, leaving you little time to work with it. It can also be too soft.

For this reason, it’s generally easier for DIYers to use ready-mixed fillers.

As with any filler, it’s important to store wood filler properly to prevent it drying out. If it’s in a tub, try pouring a little water on top of the filler (you can drain this, if necessary, when you next use the filler), cover with a piece of plastic bag and make sure the lid’s on tightly. If it’s in a tube, ensure the lid’s on properly at all times.

Even if you’re careful with storing it, fillers have a tendency to dry out once opened, so try not to buy more than you need for a job.