10" Arboricola Schefflera (Umbrella Plant)

Light
Choose a position that offers good light without direct sunlight if you want the best results, in time this will result in a neat bushy plant that will grow reasonably straight up and become tall and "tree" like.
However Schefflera is an accommodating plant for the most part so even if you choose a slightly darker home for it, things should still work out. Although it will grow slower and potentially have more of a leggy appearance as the leaves will be spaced out more. You will also have to rotate the pot a little every week or so to keep it straight, otherwise it will lean and bend towards the light source.
Some early morning or late evening direct sunlight will be tolerated, but more than a few hours a day will cause scorch damage to the leaves.
Watering
The Umbrella Plant loves to be growing in moist soil for really good growth to occur, but it will certainly accept some underwatering. So if you forget to water it for a week or two after the soil last dried out, it should forgive you.
It's not so forgiving of being overwatered though which can result in root and stem rot. Pour any excess water collected in the drip tray away to avoid this problem. In general the bigger the plant the more water it's going to need except when it becomes inactive in Winter, at which point just water enough to keep it ticking over.
So, taking the above into account, a good rule of thumb is to try and water your plant when the top inch of soil dries out. In most homes this will likely be once a week, but this could be longer if the location is cool or there isn't a great deal of light. On the flip side, bright spots with warm temperatures could have you reaching for the watering can more frequently.