I started my own practise in 1996.
You really need get indemnity insurance, which is costly before you do anything.
Then have a client base to start – so you survive. You will need at least 5 prospective clients even to consider starting.
I did consultancy work for other architects – whilst waiting to gain my own client base.
You need to decide what area you will work at.
Residential – larger number of clients
Commercial – fewer number of client but greater workload
Get drafting service numbers – for times when you need to offload
Well worth it though, work own hours.