Can you slice it for me?
'Tagliate' — stress on 'ta-GLIÀ-te'. Three syllables. The 'gli' is a palatal 'ly' sound.
Ask whenever you buy a whole loaf or large piece of bread. Most Italian bakeries have an electric slicer and will slice bread at no extra charge.
'Me lo tagliate a fette?' — 'me lo' = 'for me / it for me', 'tagliate' = you cut (plural formal), 'a fette' = into slices. The polite plural 'voi' form is used in shops. You can also say 'Me lo taglia?' (informal, to one person).
Le fette non troppo sottili, per favore.
Not too thin slices, please.
Specify your preferred slice thickness
Lo voglio intero, grazie.
I want it whole, thank you.
Decline slicing if you prefer a whole loaf
Fette spesse, per il toast.
Thick slices, for toast.
Explain why you want thick slices
The bread slicer ('affettatrice del pane') is a fixture of Italian bakeries. Sliced bread ('pane affettato') is considered slightly less fresh than whole bread — the cut surface dries out faster. Italians who buy whole bread often slice it at home with a serrated bread knife just before eating.