Biscuit decorating advice pls

I wasnt sure whether to put this on the cakecraft thread or not, they're biscuits not cake so I didn't!
I want to make and decorate camel biscuits like this but I've never iced a biscuit before! Maybe I'm being a bit ambitious? Lol
I've looked on YouTube for 'flooding' and other decorating techniques, but I just would like to know what size icing tips to buy to make those fine line patterns.
And on the subject of icing tips, I know professionals use wilton tips, but they're expensive. Where can I get decent cheaper alternatives from?
Also, what sort of tool do you think they used to draw the indented patterns? I'd really like to replicate that.
I want to make and decorate camel biscuits like this but I've never iced a biscuit before! Maybe I'm being a bit ambitious? Lol
I've looked on YouTube for 'flooding' and other decorating techniques, but I just would like to know what size icing tips to buy to make those fine line patterns.
And on the subject of icing tips, I know professionals use wilton tips, but they're expensive. Where can I get decent cheaper alternatives from?
Also, what sort of tool do you think they used to draw the indented patterns? I'd really like to replicate that.