1. You can start reading from any point as long as you are consistent. If you
start in one column, you must continue working down the numbers in that column.
2. Numbers can be read singly, in pairs (as printed), or multiples of 3, 4,
etc. Decide which you want and be consistent.
3. If you are using random numbers with a numbered grid map overlay, ignore
numbers not contained within the grid. Move on to the next relevant number. Any
numbers which reoccur that you have already used should not be used again.
4. In some habitats it may be difficult to set up numbered grids (e.g. in
woodland) and in these a 'random walk' may be used. In this method, each sample
point is located by taking a random number between 0 and 360, to give a compass
bearing, followed by another random number which indicates the number of paces
which should be taken in that direction.