Your ticket will also show how much baggage allowance you are entitled to. In most cases, this is 30 kilos, which could be one or two bags/luggage, for check-in. This is in addition to your hand carry which should not be more than 8 kilos. If the ticket indicates “one-piece concept”, this means that you are only allowed one luggage and should not exceed 23 kilos. If going to the US, there are airlines that have specific dimensions or sizes for the luggage.
Check also with the airlines as to the requirements in locking your luggage as there are rules applicable; e.g. in US, it must be TSA (or Travel Sentry Approved) lock while some countries do not encourage the locking of luggage. Put an easily seen or identifiable mark in your luggage so that you can easily locate them; e.g. put a lace or ribbon in the handle. You can put your name and contact information in the luggage but do not make it so big that can easily be visible and traceable to you. Emerging modus operandi for drug trafficking use identifiable or marked luggage in transporting drugs.