The men and women we seek to honour and portray were professional Soldiers, Sailors, Airmen/Women and Service Personnel. Whether they spent a long or short period of their lives in military service, they deserve the same respect. Therefore if you wear a uniform and rank, wear the uniform with pride and BE the rank.
Learn as much as you can about your position and act accordingly.
Your uniform and the way you dress should be as immaculate as military regulations and standards that were expected at the time and strive to look and act the best you can.
Alternatively, combat uniform should look combat ready or combat stressed.

Professionalism is also reflected in personal and military bearing, the sharpness of a salute, the shine of his or her shoes, posture and pressed uniforms all add to the air of military personnel.
There is no excuse to use terms such as "It's only a hobby".
  When one is part of an organisation teaching and depicting military
history and personnel, do not minimise your role in any way.
General George Patton said, " If a person does not look like a
soldier, then how are they supposed to act like a soldier."
Part of your profession or hobby is to demonstrate how service
personnel acted when wearing their rank, their uniform and
serving their country at this period in history.

Being Professional is also reflected in how you interact with others.
A professional does not criticise or call out people personally or in other organisations
for lacking in their impression, be it because of their lack of experience or by choice.
You should serve as an example and if others take notice and follow, all the better, but this takes maturity and comfort in ones own role.

If a professional, should lack skills or attributes in drill or any other military technique, then their professional manner may make up for this and may also drive them to learn what skills they lack.

Individual professionalism is noticeable by everyone and in the public setting, professional Historical Interpreters, Re-enactors & Historians stand out simply due to the look of their uniform, their posture and the way they carry themselves.
This may be your hobby or your profession and if you strive for professionalism it will be noticed.

Whilst many wish to use Historical Interpretation and Re-enactment to teach and keep history alive, our profession and hobbies can be expensive and one may attempt to source as much original material and uniforms as is feasible and build up their inventory over time which is a valuable resource, however what is also essential is dedication, integrity, respect and professionalism, as we are honouring those that sacrificed so much and many that gave everything for our freedom.