A sketch book is a record, amongst other things, of the places you have visited, the ideas you have had and what you have seen.
If you use each page as you go along, without skipping any, you will also have a record of your development. I would advise you to fill up the book completely, dating the drawings as you go and only then starting a fresh book. In this way you will have a sense of achievement and it will give you endless pleasure to look back over what you have done.
A sketch book can be stored easily on a shelf and it is pleasant to see the finished sketch books pile up, containing a record of what you have done over the years. For this reason I don't advise that you go out with a few odd sheets of paper pinned to a board. The wind will spoil the paper in no time at all and the board will tire your arms after only a few minutes. Even with a sketch book it is good practice to clip or hold down the edges of the pages with an elastic band to stop the wind from whipping them up. It is most frustrating to have the paper turn over and spoil a wash because you haven't taken the simple precaution of holding the page down.
A sketch book can contain finished paintings, quick sketches and even written notes and the more you fill up the pages the more interesting they will appear to anybody who is having a look at them. It isn't necessary to be too neat and tidy in them. Let your mood dominate what you do. In this way each page will have something different to say. And if you make one or two drawings that don't quite come off, leave them there also. These drawings too will have their place in the pattern of your development shown in the sketch book.
FILLING YOUR SATCHEL
It is unlikely that you will know beforehand what sort of reaction you will get from a subject that you haven't seen before. And so you will not be too sure whether it will be best to draw it in conte or carbon, or pen and ink, or whether to do a full-blooded painting. This means that whenever you start out you should be prepared to do any of them.
Being ready to meet all emergencies with a selection of different media will give you a freedom of choice and consequently enable you to do yourself justice with what you see.
The less you limit yourself the better will be the result and because you will need a variety of media to work with, they must be selected with care. An ordinary pen and a few nibs, a bottle of ink; a stick of conte or a carbon pencil, a razor blade or two, a piece of rag; three or four colors at the most plus white, in a box that you can use as a palette; a plastic bottle for water and not more than three brushes should cover most contingencies and not be too heavy to carry in your satchel. If you have room, a small box of pastels can be added. With this selection you will be able to draw or paint without any of the frustration which comes because you only intended to draw and found that you would rather paint and left your paints at home. It won't matter what sort of mood you are in. If you always take the precaution of taking along a selection of materials you will be able to suit that mood.
Don't let your sticks of conte float about in the bag. Keep them and your pencils and brushes in a box. The ink and the waterbottle will slip into the pockets of the satchel and the rag will hold the ink steady so that it doesn't move about. I don't advise taking charcoal as it is too fragile and messy. Keep your razor blades wrapped up and don't let them get near your brushes. The jogging about might cut them into ribbons.