CIS is only applicable to the construction industry and there are three main types (CIS4, CIS5 and CIS6) but basically two styles - paid gross and paid net (CIS tax on the labour content is deducted before you are paid - but you can offset it against your PAYE returns so you don't lose out).
Registering for VAT after you've reached the limit of £67K of taxable supplies (basically your turnover in your case) is not a problem but don't leave it too long as there are nasty penalties. You can also register for VAT straight away if you believe you will have a turnover of £67K in your first twelve months which can be handy when buying new kit as you can claim the VAT back
. But beware, Revenue & Customs are becoming very efficient and surcharges are severe so keep on top of your VAT returns otherwise you'll receive an assessment which can be of crazy amounts plus 15% surcharge and payable on demand until you submit a return.
If you make a loss and submit a negative return expect a VAT Visit if it's over £8K - these can also be a pain.
If you purchase equipment on a credit basis and don't pay the supplier within 6 months then HMRC can make you repay the VAT you claimed back and they are starting to enforce this a lot. However, if you have not been paid by a customer after six months but have paid the VAT then you can claim the VAT back - but HMRC won't shout about this and you need to be on the ball yourself - obviously.
HMRC will also look at your turnover on the VAT returns and compare this to your Annual Financial Accounts to make sure you are not evading any tax.
VAT in principle is actually quite straight forward but if the above seems like a foreign language then as mentioned already I'd definitely advise getting an accountant but my strongest advice would be to go by recommendation. There is a lot of very bad accountants out there.
The accountant who I took over from was awful and it's taken me over a year and cost the company almost quarter of a million pounds to sort out his mess. We found out a little history on him from his past here:
http://news.bbc.co.uk/1/hi/scotland/1342914.stm 
He never served the jail sentence because the police forgot to pick him up.
So please be super careful with who you trust your finances with.
It may also be prudent to set yourself up a limited company as you can then enjoy the benefit of limited liablitiy. In other words you as a Director are safe and only the company (which is seen as a separate entity) can be sued etc. It keeps your personal assets safe unless you use them as a personal guarantee and basically there'll be a floating charge held against them which will crystalise and become a fixed charge should the company get into trouble.
However, you aren't completely safe through operating a limited company - as a Director you must still operate with Due Dilligence and with honesty and basically within the law. You are also personally liable for your own tax (PAYE and NI). There are some statutory requirements also with a limited company. Also, you will be subject to Corporation Tax (tax on your profits), however, this is basically the equivalent to being taxed on your income as a sole trader.
Public Liability insurance is a must, even if trading as a limited company. Not only will it protect you but you may not be able to secure contracts without it.
A business plan will be necessary to open up a business bank account but it can be pretty basic unless you are seeking to obtain credit, ie. a loan or overdraft facility.
Probably the most important part is marketing. Everything above is a waste of time if you aren't generating business. Personally, I'd get someone good and pay for it! This will let you focus on what you do best - the creative side!!!
One last thing, if you are expanding etc be super careful about who you employ. If growth may be temporary then try to sub-contract wherever possible before taking on staff. Employees are becoming close to untouchable these days and a bad employee can be a major hassle and also cost you a lot of money.
Some of the factors that employees can create include:
Age discrimination, sex discrimination, disability discrimination, unfair dismissal, no contract of employment (or statement of particulars) which is an instant payout if not given within two months and the list goes on. I was just informed by a law firm in Edinburgh that unfair dismissal can lead to claims to a limit of £60K (ouch) and there's not limit to disability discrimination.
Oh, if you sub-contract be sure to keep the contracts they do varied and the hours they work random or they'll fall within employee rights.
On a positive note, get down to Business Gateway, there'll be a fair amount of forms to fill out etc but you can get £1K startup and possibly more if you are a woman and also if you fall within certain age categories but the grants are drying up fast. I know it's only £1K but I wouldn't turn my nose to a grand! lol
Hope this helps.
Graham
Excellent advice.
