Taken from my own thread. https://www.fsegames.eu/forum/index.php?topic=25429.0 Note these are from 1815 but they look nice :P.
The United Kingdom
The British Lieutenant and Ensign shared the same shoulder epaulettes and the Captain is denoted by his tassels being thicker then the Lieutenant and Ensign's ones. The Company officer ones are not for all regiments, many had different versions due to different facings or other reasons. Some regiments has silver officer epaulettes.
Many Regiment used silver epaulettes instead of gold. Why they did I have no idea.
There was also a Colour Sergeant for Rifles.
Contrary to the belief of most people on here Staff Corporal and such where ranks only used by the horse gurads. Sergeant and such was used by most Cavalry regiments
Ranks
Officers
Line Regimentals/Battalion
(https://i.imgur.com/OsnHEfB.png) (https://i.imgur.com/qY6chdV.png) Colonel
(https://i.imgur.com/Z4l1Pq5.png) (https://i.imgur.com/HLGx4Uf.png) Lieutenant Colonel
(https://i.imgur.com/B2JpBdf.png) (https://i.imgur.com/TPTEgld.png) Major
Company Level
Centre Company
(https://i.imgur.com/ZidX4oS.png) (https://i.imgur.com/fvDj9Kd.png) Captain
(https://i.imgur.com/3NzcXQN.png) (https://i.imgur.com/IACcSpZ.png) Lieutenant
(https://i.imgur.com/3NzcXQN.png) (https://i.imgur.com/IACcSpZ.png) Ensign
Grenadier Company
(https://i.imgur.com/AnH2LuF.png) Captain
(https://i.imgur.com/v07KgzO.png) Lieutenant
Light Company
(https://i.imgur.com/Z259t0X.png) Captain
(https://i.imgur.com/lYMtCf0.png) Lieutenant
NCOs
(https://i.imgur.com/1UywlyL.png) Serjeant Major
(https://i.imgur.com/bQ4LJJO.png) Colour Serjeant (Line)
(https://i.imgur.com/h9C1PzV.png) Colour Serjeant (Foot Guards)
(https://i.imgur.com/NzMWQyR.png) Colour Serjeant (Rifles)
(https://i.imgur.com/qSkUVJC.png) Serjeant
(https://i.imgur.com/OEr7Ri7.png) Corporal
(https://i.imgur.com/cxHdnPA.png) Lance Corporal