I would think very carefully indeed before entering into a partnership, with anyone. You will both be equally responsible for any debts that the business may incur. Most start off needing both signatures for transactions but then the logistics of this mean that they end up, for instance, with a few cheques signed by one of them, ready for use. Also, you will both get any profits in proportions according to the agreement. If you are a sole trader with your friend as an employee you are in full control of the finances but are obliged to pay his wages and you will be left with the profit if there is any.
If you start with a ltd co you will both be employees of the business, your personal assets will be safe (unless you put them up as surety against overdraft or loan agreements, etc). The profits will belong, after tax, to the share holder(s).
The above is very brief and IMO if you do not know the fundamental differences between the types of business you will probably not be able to run your business properly.
Do not make the mistake of thinking that if you are busy you will be making a profit, it doesn't necessarily follow!