Like Mark said, the accounting records is not the place to "provide" for future expenses and income which hasn't yet occurred. Your accountant will tell you that such provisions for future expenses/income is contrary to formal accounting standards (IFRS, IFRS for SMEs, SA GAAP).
Accounting records are prepared according to the accrual concept, therefore doesn't always match up with the physical cashflows. As Mark said, make use of a cash budget (likely in an excel spreadsheet) which you update on a regular basis, but also compare your previous budgets to your historic figures, so that your can fine tune your budget.
A small correction with your accounting for provisional tax:
The payment of your provisional tax is not an expense (yet). It is a prepayment of tax.
The correct way of accounting for the payment of provisional tax (your journal 7) would be:
Dr Receiver of revenue (balance sheet account)
Cr Bank (balance sheet account)
When year end comes along, and your calculate your income tax payable for the year, and complete your tax return your recognise the tax expense:
Dr Income tax expense (income statement account)
Cr Receiver of revenue (balance sheet account)
By accounting for tax like shown above, your "Receiver of revenue" asset/(liability) on the balance sheet correctly shows how much you how much you owe SARS at year end.