The Cosmetics Products Directive requires that a PIP be assembled prior to marketing a cosmetic product
A Trading Standards Officer (or Government official in some countries) can inspect a PIP file at typically 3 days notice.

There are eight important parts of a PIP file as listed below:

1. Product formulation with % of each ingredient
2. Raw material specifications, including a microbiological specification. It is useful to include the MSDS sheets here.
Note: a specification is a summary of product characteristics such as viscosity, appearance, colour, odour, pH etc
3. Outline of Manufacture, i.e. typically 5-6 lines minimum of text giving an idea of the processes, no need for excessive detail. However it is a good idea to describe the hygiene and good manufacturing procedures.
4. Finished product specification, i.e. similar to raw material
specification, with appearance, microbial purity, pH, viscosity, odour etc, (where relevant)
5. A Safety Assessment made by an EU approved Assessor
6. Details of Safety Assessor, e.g. CV
7. File to support Proof of Claims, usually important if making SPF
claims, anti-wrinkle claims or claims where numbers are involved, e.g. "washes twice as clean"
8. File of complaints of harm to human health, e.g. skin irritations etc. This will be an open file, ready to receive any complaints.

The above is a guide only and the amount of detail required will vary according to the nature of the product.
Remember it is important to follow the requirements for pack labelling, including weight, address of supplier, period after opening symbol (where relevant) and ingredient labelling. The ingredient label must include any of the 26 potential allergens that are naturally found in many essential oils and in most fragrances (see resource 'Allergen Calculation').