Juice Pourers and Storers
Using cartons of orange juice, Pineapple juice and so forth is OK at an 'ordinary' party, however to be professional, be able to pour faster, more accurately and look good, the answer is Juice Pourers/Storer.
Each Storer holds up to 1ltr of prepared mixers or juices. They are colour co-ordinated - so orange for Orange juice, white for say Simple Syrup, Green of Apple juice and so forth. The pouring lid unscrews and a cap can be screwed on in place thus keep the contents reasonably air tight. Keep the Storer in the fridge until needed. They are beautifully balanced and are a joy to use.