I read that gg is a geminated or lengthened consonant - I also have read that before i, g is made into the affricate. Do I make it into a geminated affricate?
In Italian the letters gi may form a digraph that denotes the affricate pronunciation /d͡ʒ/ before a, o or u. Before e or i, the consonant g is pronounced /d͡ʒ/. In all the following words, there is the affricate:
giacca gioco giusto gente ginestra
To be clearer, gi is a digraph only if another vowel (a, o or u) follows. However, it is not a digraph if the i is tonic (like in pubalgia or leggii, plural of leggio).
In the first three words there is no /i/ sound.
When the affricate is geminated, it is written gg (before e or i) or ggi (before a, o or u):
roggia messaggio laggiù aggettivo raggi
The surface pronunciation of the affricate /d͡ʒ/ may vary depending on the speaker’s variety of Italian, in particular for the geminated one that can even become very similar to /j/; pronouncing /d͡ʒ/ as [ʒ] is not at all uncommon in central Italy (some parts of Tuscany, for instance). In southern Italy, /d͡ʒ/ is commonly geminated also when standard Italian would prescribe no gemination.