Just a reminder: while the most suggested case is the best solution, note that if you don't close with a brake; your case:, it will continue executing in the next case.
Then, while it's still best pratice to break your cases, you could still adopt a solution similar to the following:
switch (orderType) {
    case 3:
        someMethod1();
    case 2:
        someMethod2();
        break;
    case 1: 
        someMethod1();
        break;
    default:
        break;
}
Note that "avoiding breaks" solution can't completely cover OP necessities, because writing:
    case 3:
    case 1:
        someMethod1();
    case 2:
        someMethod2();
    default:
        break;
or:
    case 3:
    case 1:
        someMethod1();
        break;
    case 2:
        someMethod2();
        break;
    default:
        break;
would make case: 3 be the same than case: 1, making them execute both methods in first code, or a single method in the second code.