var method = typeof(...).GetMethod(...);
// or
var method = delegate.Method;
// or
var method = (DynamicMethod)(/* create or get method */);

IILReader GetReader(MethodBase method) {
    IILReaderConfiguration cfg = Configuration.Resolve(method);
    return reader = cfg.GetReader(method);
}

foreach(IInstruction instruction in reader) {
    var opCode = instruction.OpCode
    object operand = instruction.Operand;
    int ILOffset = instruction.Offset;
    // ...
}

Func<...> someFunc = ...; // Just use it while debugging

class Bar {
    public void Stub() {
        throw new NotImplementedException("Stub");
    }
}

var method = typeof(Bar).GetMethod("Stub");
var reader = GetReader(method);
// use default pattern or create you own
var pattern = Analyzer.NotImplemented.Instance;
if (pattern.Match(reader)) {
    // do something
}