Steps of construction:

1. Draw 3 non-collinear points, say, A, B and C such that none of them lies on the same line.

2. Form a triangle ABC by joining AB, BC and CA.

3. Construct a Parallel line to AB

Choose B as a centre, draw an arc cutting BC and BA at W and V, respectively.

Choose C as a centre and draw an arc on the opposite side of BC to cut BC at P. (Note: use the same radius as in the previous step)

With centre P and radius equal to WV, draw an arc cutting the arc drawn in the previous step at Q.

Join CQ and produce in both directions to obtain the line parallel to AB.

4. Construct a Parallel line to AC

With A as centre, draw an arc cutting AC and AB at T and U, respectively.

With centre B and draw an arc on the opposite side of AB to cut AB at X. (Note: use the same radius as in the previous step)

With centre X and radius equal to TU, draw an arc cutting the arc drawn in the previous step at Y.

Join BY and produce in both directions to obtain the line parallel to AC.

5. Construct a Parallel line to BC

With B as a centre, draw an arc cutting BC and BA at W and V, respectively (already drawn).

With centre A and draw an arc on the opposite side of AB to cut AB at R. (Note: use the same radius as in the previous step)

With centre R and radius equal to WV, draw an arc cutting the arc drawn in the previous step at S.

Join AS and produce in both directions to obtain the line parallel to BC.

6. Your construction is ready.