When looking for a suitable place to build your base try to choose a defensible position. For example up against a cliff face, or tucked into a recess but more importantly make sure the area is not swamped with predators.
Whatever location you decide on it is important to make sure the spot offers easy access to resources such as wood, thatch, fibre, and stone. In general it is best to move inland a little, away from the often heavily-populated coast as the beaches won't yeild much in the way of resources and they tend to be patrolled by hostile tribes.
Make sure you check there are no tribes nearby as some do not like strangers setting up camp within their territory. If you find the ideal location but discover there is a tribe nearby you need to approach and discuss the situation with them to see if they will give you their permmission to build your base on their land.