I am a criminal sentenced to exile in Australia in the year 1800. After disembarking from the transport ship, what can I expect my life to be like?

"Here's one we prepared earlier!"

This account is taken from the period around 1810 to 1820, rather than 1800. I have a couple of reasons for choosing this period:

It was the time that Governor Macquarie reformed the way things worked for convicts, by implementing some more progressive policies.
I’ll be relying (in part) on a report written in 1822 about the conditions for convicts in New South Wales.
There were more free settlers and ex-convicts around by now, to change Australian society.

However, I won’t be writing a first-person account, as you've requested – quite frankly, I don’t want to compete with Marcus Clarke’s ‘For The Term of His Natural Life’ which has done this far better than I could ever hope to.

So, what was it like for a convict landing in Sydney in the 1810s?

Firstly, when their ship arrived, all convicts mustered before disembarking. This was almost like a stocktake.

Each convict is asked his name, the time and place of his trial, his sentence, native place, age, trade and occupation; [...] After ascertaining the height of each convict by actual admeasurement [...] as well as the colour of the hair, eyes, the complexion or any particular mark that may tend to establish the identity of each convict, an inquiry is made respecting the treatment that each has received during the passage [...] and lastly, whether he has any body ailment of infirmity.

[Bigge, 1822]

The Superintendent of Convicts would then determine the destination of each convict.

In the early days of the settlement, convicts would work directly for the colonial government: making roads; building residences and public structures; cultivating farms; and so on.

The convicts in the service of Government, are divided into gangs, – every gang has an overseer, and every two or three gangs a superintendent; these are frequently chosen from amongst those convicts who best conduct themselves. They work from six in the morning till three in the afternoon, and the remainder of the day is allowed to them, to be spent either in amusement of profitable labour for themselves. [...] Should the convicts misconduct themselves at their work, the superintendents have no power of inflicting punishment, but are for that purpose obliged to take them before [a magistrate or court who] may order a punishment of 25 lashes [or] as many as 300. [...] Another mode of correction [...] is to sentence the culprit to work for a certain number of days in the gaol gang; he is here obliged to labour at some public work in irons, from six in the morning to six at night, and no hours are allowed to him for profit or amusement.

[Select Committee Report, 1812]

Notes:

The convict overseers were known as “trusties”.
The gaol gangs were also known as “chain gangs”.

By the way, flogging was harsh:

[A convict was sentenced to] 50 lashes. Blood flowed at the 4th; the convict cried out at the 18th, and continued crying for a few succeeding lashes; his skin was considerably torn, and blood flowed during the whole of the punishment. This man groaned much, and prayed whilst suffering his sentence; [...] I am of opinion that he was sufficiently punished at the 25th lash

[Appendix to Select Committee Report, 1837]

Starting in the 1800-10 period, convicts were more and more often assigned to work for free settlers, as farmhands or domestics (the latter was often where the women ended up – if they didn’t go to factories to do sewing work). This was seen as being a good opportunity to rehabilitate the convict, by giving him or her exposure to good civilised Christian people to reform his or her character, and also by separating him or her from the bad influence of other convicts. And, it seemed to work – convicts who were assigned to work for settlers often did end up better off than convicts who stayed in the government barracks. Conditions were usually better for an assigned convict, too:

Convicts in the employment of the Government are generally worse off than those assigned as servants; they are employed chiefly on the public works of the colony; some of them are, however, in situations of comparative ease, such as clerks, messengers, constables in the police and so forth

[Select Committee, 1837-8]

The convicts’ treatment in their assignment would depend entirely on their master. Some masters were rigid and punitive, some were enlightened and compassionate. There are accounts of convicts becoming beloved members of some families, while other convicts lodged complaints with the Governor about cruel mistreatment.

Because, despite their status as criminals, convicts had equal access to the law as free persons. This was partly driven by necessity as, in the early days, magistrates weren’t able to try cases in court if they couldn’t take evidence from convicts – there weren’t enough free people around! So, through sheer necessity, convicts had to be treated as equal under the law even though they were criminals.

While on assignment, convicts were also permitted to work for themselves when they weren’t required to be working for their assigned master, like the ones in government service. Of course, it might be a bit difficult to earn a living if you were assigned to work on a farm 100 miles from the nearest major town!

However, convicts who behaved badly on assignment could be punished, by floggings, or by being assigned to road parties building roads.

Convicts were also eligible for tickets of leave. This was a kind of conditional pardon, which allowed convicts to go out and work for themselves to earn money. It was given to convicts who had behaved themselves well during their sentence, but only after a minimum period: convicts on a seven-year sentence were eligible for a ticket of leave after four years; convicts on a fourteen-year sentence, after six years; convicts sentenced to life, after eight years. They still held the legal status of “convict”, but were free to work for themselves until the end of their sentence.

At the end of their sentence, ex-convicts (“emancipists”) were often offered free land if they chose to settle in Australia – which many did.

Despite all this, it was still a hard life, and brutal at times. But, many ex-convicts did well for themselves, becoming traders, farmers, novelists, newspaper editors, even judges. Some became rich. Some became leading lights of later society.

Sources:

J.T. Bigge: ‘Report of the Commissioner of Inquiry on the State of New South Wales and its Government, Management of Convicts, their Character and Habits.’ 1822 [John Bigge, a judge, was sent to Sydney in 1821 to see conditions for himself, and report on them]
Report of the Select Committee on Transportation. 1812
Report of the Select Committee on Transportation. 1837-8