Check the venue's own guidance
Read the booking information for any dress requirements, bag restrictions or cloakroom details. Different venues and events have different arrangements, so do not assume a service will be available because you used it elsewhere. A small amount of checking can save you from carrying an unnecessarily bulky coat or bag.
Choose the outfit for the kind of evening you have planned. Trousers with a shirt, a knitted dress or familiar separates can all make sense when the venue permits them. If dressing up is part of your enjoyment, allow yourself that choice; if you prefer simplicity, concentrate on fit and condition rather than adding formal pieces for their own sake.
Make the layers manageable
Try sitting with the coat folded on your lap or over your arm. A very long or padded coat can become awkward if there is little spare room. Where the weather allows, a less bulky outer layer with a cardigan underneath may be easier to handle. Keep the cardigan accessible rather than at the bottom of a packed bag.
Look at any accessories that might catch on a neighbouring seat or make a noise when you move. A large bag, several loose bangles or a long scarf may be fine, but test how they behave in a confined space. Choose pieces you can settle once and then forget about.
Dress for the walk as well
Work out the route from your transport stop and check the forecast before leaving. Shoes should suit that distance as well as the outfit. Put tickets, phone and keys in an easy-to-reach place so you are not unpacking at the entrance. The most successful combination lets you enjoy the performance without spending the interval managing your clothes.
