I am composing a piece on Sibelius (free demo/trial version) for my music coursework but so far it’s proving to be somewhat nightmarish – I can’t make head or tail of it, the manual is rubbish. Does anyone know how to add dynamic/articulation markings (legato, piano, staccato, cresc etc.) on it? Thanks loads 
I use Sibelius everyday of my life – I am an arranger of classical music – and I think your problem is that you have the DEMO version – many things are disabled. Can you even SAVE or print in this version? My knowledge is good on the REAL version – but I never bothered with the demo.
If you need FREE – did you investigate Finale Notepad? (www.finalemusic.com) Yes, it is also limited, but I was *told* that this free version is NOT as limiting as Sibelius. I know that dealing with these at the beginning is not easy – steep learning curve! – but in the long run, you will be gratified. I am so sorry that you are struggling now – this is SUPPOSED to make your work easier!
ADDED – right-click does not bring up enough menu choices. I LEFT lick on the note, then hit Control+E – and then type in the expression text I want – which includes dynamics. It does NOT attach them to the SCORE, but only to the part. So – if I want them universal in the score, I highlight and copy (Control+C) that dynamic I put in, and then paste them (Control+C) in each part Easier than doing the first thing I told you – l-click, Control+E, type text, etc. for EACH part.
The online directions say you can hit Control+mf, for example, and get mf in the score – NOT! I get a Find box. Several of these things are being fixed in the new Sibelius version (my son has a MM in Digital Music, and at a workshop with The Big Guys from Sibelius, they showed him the update stuff.)
This is an amazing program- but not ALL the little *random features* are totaly worked out. Hang in there! But I have NO FAITH WHATSOEVER in a demo, except for Finale Notepad.