Many factors influence the placement of adjectives in Spanish. A few of these are:

• Stylistic choices or psychological nuances: Subjectivity, etc - No son leyes sino tendencias
• Mode of language usage:
• Colloquial or formal spoken
• Casual or formal written
• Prosaic or poetic
• Contrastive or enhancing - Informational content of adjective – technical, nationality, contrastive, etc
• Single or multiple adjective(s)
• Parallel or Non-parallel adjectives
• Mobility factor – High or low mobility
• Rhythm and Mobility
• Courtesy formulas
• Length of adjective - esdrújulas, etc
• Whether we need a prepositional phrase or adjectival clause to do the job

It is difficult to reduce adjective placement to a formula as we can with prepositions and cops.

Note: articles, numbers, and demonstratives are also adjectives and their position is fixed:

• La hermosa casa
• Dos hermosas casas
• Esta hermosa casa

Parallel

Parallel adjectives tend to be set off by commas and are connected by "y".

Mi generoso y leal amigo. Mi amigo generoso y leal.
My generous, loyal friend.

El gracioso y culto diplomático.
The witty, cultured diplomat.

Un administrador competente y experimentado.
A competent, experienced administrator.

Non-parallel

Nuestro sistema educativo actual.
Our present-day educational system.

El piloto australiano alto.
The tall Australian pilot.

Aparatos electrónicos japoneses.
Japanese electronic devices.

Mi generoso vecino mexicano.
My generous Mexican neighbor.

La literatura medieval española. or La literatura española medieval.
Spanish medieval literature.

El gracioso diplomático británico.
The witty British diplomat.

El santo imperio romano.
The Holy Roman Empire.

Una respetada universidad francesa.
A respected French university.

Two non-parallel joined by “and”:

Una obligación social y moral. - Social and moral obligation.

Non-parallel but Noun and adjective seen as a unit.

mármol africano negro or mármol negro africano - black African marble