For cleaning I generally just use the hose with nothing attached to rinse off, or sometimes the standard hose brush that is very soft and leave it at that.
For deep cleaning prior to treatment I vacuum it then when wet with cleaner use a very soft nylon nailbrush to gently work the cleaner.
For general dry removal of bits the lint roller (5 for £5 at Costco)
At all times my concern is to avoid 'piling' the fabric through any excess rubbing, etc.
Prevention is the key though with biannual use of Ragtopp and it still looks brand new after 7+ years