When renovating a bathroom, it’s easy to get lost in the details of shower and bath installation, even though most people only shower or bathe once or twice a day. Meanwhile the basin gets neglected, even though it will get used frequently after the renovation. A good basin is the workhorse of every bathroom, so it’s worth taking some time and planning it out properly.
Basins come in three styles, free-standing, semi-recessed, and recessed, although some basins might challenge those definitions. Freestanding basins are both the trendiest option, and the easiest to install, requiring a minimum of countertop alterations. It’s always best to install the basin at the same time as the taps.
For the planning stage, use a marker or some chalk to plan out the basin placement, and go over any manufacturer’s instructions that come with the unit. Make a cardboard template of the counter, basin and taps, so that everything works out perfectly.
After installing the basin and connecting the water, give it a little test wash to see if there are any leaks. If not, that’s great, but don’t use it again until all sealants and adhesives have set.
Source: http://greatbathrooms.hubpages.com/hub/Countertop-Bathroom-Sinks-Some-Installation-Tips