Insert the tips of two thin rods into the split as in the diagram below and take one of the rods to the front and the other behind three sticks and out to the front as in the diagram below.

Take the left hand rod (weaver) to the right in front of three base sticks, over the right hand rod (weaver), behind the next three base sticks and out to the front again.  Now turn the whole base through 90 degrees anticlockwise (to the left) and repeat the process taking the left hand weaver in front of three sticks, over the new right had weaver, behind the next three sticks and out to the front again.  Again turn the whole base through 90 degrees anticlockwise and repeat the process.  Continue doing this until you have been round the base two times.  You have now tied in the slath.
You must now open out the base sticks like the spokes of a wheel.  Turn the whole base through another 90 degrees  Take the left hand stick of the next  group of three and pull it to the left.  Now take the left hand weaver in front of three. over the right hand weaver. behind the stick which you have just pulled to the left and back to the front again.  The next stick of the group is left straight but the one on the right is pushed to the right.  Once again take the left hand weaver in front of one stick this time,  behind the centre stick (the one you left straight) and back to the front coming out in the gap between the centre stick and the right hand stick..  Repeat this process round the base so that all the sticks are now separated into the spokes of a wheel.  Continue in this manner until you reach the end of the weavers.  As you weave round the base you must try to bend and separate the stick as evenly as possible and try to introduce a "crown" on the base as you go.  Bases are usually made to be convex like a saucer.  This is known as the crown.  The reason for the crown is to add strength to the basket and  to give the basket an edge to sit on.  You achieve this crown by pushing each stick away from you as you weave round it and by pulling down harder on the weaver at the back.  You should now have something like the picture below.

It is now necessary to join in another two weavers.  Take the butt of the left hand weaver and pull it up and  towards the right a little to  make a hole between the right hand weaver and the right hand stick.  Push the butt of a new weaver through this hole so that you have a butt end coming out of both sides of the base.  Make sure that the butts lie against each other.  Use the new weaver to complete a stroke i.e. take it in front of one stick to the right and then behind one leaving it at the front.  Pull the next butt up and make a hole similar to the previous one and insert the next new weaver. Use this new weaver in the same way and continue until you reach the end of these new weavers.  These  will end with tips but just join in the same way tip to tip.  Continue working joining butts to butts and tips to tips until you the base measures about 7 or 8 inches across.  On your last round try to end with tips which can be tucked under the previous row of weaving.
Cut off  all the ends of the sticks as close to the base as possible and trim off all the ends from the basket with a knife or secateurs making sure that the remaining rods lie against something and that you have not cut them so short that they push through to the other side of the base.  This completes the base.  Larger bases will require more sticks 7, 8, 12 or more and there are different ways tying in the slath and weaving the base.  The weave described above is called pairing.