There are two choices for bending the aluminium.
Use a proper bending tool that can be bought fairly cheaply. It will have limits on the size you can bend. It will give a decent straight bend. There are details of how to measure where you bend to get accuracy. You could make your own and you tube has examples (some are crude ). Also, how tight a curve do you need in the bend? This is where you can make things easier or more difficult in getting dimensions accurate! Bending over a rounded or curved former can do this to avoid tight bends, even just pressing the sheet by hand in some cases.
You can use a mallet or hammer but that takes practice to get a good finish.
As regards the different strength depending on direction....it is standard practise to test strips using samples taken in both directions during rolling. Tensile strength is the one that shows differences. Hardness is unaffected as it is on a specific point that orientation doesn’t affect. Bend tests will show small differences that will depend on the rolling temperature and amount of thickness reduction.
