The Quick Line: Line First, Colour Second

In urban sketching you rarely have as much time as you'd like: the tram is coming, the café is closing, the sun keeps moving. The answer isn't to "paint faster" but to follow a tried-and-tested order: line first, then colour. In this lesson you'll practise exactly that.

Why the line comes first

A line drawing gives your picture an immediate framework. Windows, doors, people, bicycles – with a fineliner, all of it lands on the paper in seconds, long before you even think about colour. That has a practical advantage: even if the layer of colour doesn't turn out perfectly later on, the line carries the picture. And a mental advantage: you make the compositional decisions – what goes on the page, what you leave out – separately from the question of which colour belongs where. Solving two problems at once is almost always overwhelming; one after the other is far easier.

Ten minutes, one fineliner

Set yourself a firm time limit for the line drawing, ten minutes for example. That sounds tight, but once you're used to it, it's perfectly enough for a street café, a building façade or a market stall. Start with the largest shapes – the roofline, the row of windows, the silhouette of a tree – and work your way towards the details. Don't begin at the top left and plod all the way to the bottom right; jump between parts of the picture, just as your gaze actually roams across the scene.

Ten minutes also makes sense because not much usually changes in the scene during that time: the coffee drinker is still sitting there, the light still falls much the same way. Wait any longer and you'll end up drawing a scene that no longer exists.

Search for contours instead of correcting them

The biggest brake on beginners is the eraser. Instead, search for the contour the way your eyes search for an edge: slowly, feeling your way, with short, observing strokes rather than a single hastily drawn line. If a line isn't quite right, simply draw the corrected line next to it instead of erasing the first one. The viewer's eye automatically picks out the right line, and you lose no time.

These messy, repeatedly searched-for lines are not a flaw, they are the style of urban sketching. A crooked roof edge or a double-drawn window reveal tells us that someone stood there on the spot and observed – unlike a technically perfect but sterile line drawn with a ruler. Allow that liveliness instead of correcting it away.

Colour: loose washes over the line

Once the line is finished, colour comes next – and deliberately loosely. Mix plenty of water into the paint and lay in broad, simple areas: a façade, a piece of sky, a canopy of leaves. The fineliner has already done the fine work, so the colour may happily run over the line or leave gaps before it. It's precisely this interplay between the exact line and the imprecise colour that gives the technique its charm. Between individual washes, wait until the previous one has dried a little, otherwise the colours will bleed into each other uncontrollably.

Line-and-wash or pure watercolour sketch?

There are two basic types of watercolour sketch. With "line and wash" you first draw everything with the fineliner and then lay colour over it – the line stays visible and carries the picture, the colour merely complements it. With the pure watercolour sketch you leave out ink altogether and work solely with the brush; form and contour arise from areas of colour and their edges alone. This second method often looks more painterly and atmospheric, but it demands more experience with water and brushwork, because every line is also a colour decision. For getting started, line and wash is the more reliable route, because the fineliner gives you a safety net.

Exercise

Sit for 20 minutes at a window or on a bench with a view of a street scene. Set a timer for 10 minutes and draw with the fineliner only, without an eraser and without a pencil underdrawing. When the time is up, put the fineliner down, however far you've got. Then take another 10 minutes and lay loose washes over the drawing using no more than four colours. At the end, notice which lines you like best – usually they're the imperfect ones.

Key points

Line first, then colour: that gives every sketch a solid framework. Don't erase – just search for the right line again alongside. A messy line with life beats a perfect line with no character.