[Parameter] explain how to obtain an Parameter object; link to Signature

Author: moritz

lib/Parameter.pod

@@ -6,6 +6,16 @@
 
 Represents a parameter, for purpose of introspection.
 
+The usual way to obtain a Parameter object is to create a signature,
+and call C<.params> on it to obtain a list of the Parameters.
+
+    my $sig   = :(Str $x);
+    my $param = $sig.params[0];
+    say $sig.type;              # Str()
+
+See L<Signature> for more information, and also for an explanation
+on what most of the concepts related to parameters mean.
+
 =head1 Methods
 
 =head2 name