Can anyone help with some Sibelius questions?

I'm trying to input a tuplet through step time.  I would like the rhythm to be:

1 8th note and a 3 note 16th note triplet.  When I try to do this right now I put in an 8th note and then tap ctrl 3 to set the tuplet, click the 16th note and when I look up I see an 8th note triplet begun.

Can anyone help me please?

If I'm understanding you correctly, you need to input your 8th note, then input your 16th note on the ";and";, then with the 16th note still highlighted, hit ctrl+3 to start the triplet.

A triplet will start with whatever note is highlighted.

Hope that helps.

Keith is dead on!