In full time employment and start a part time business

Bomber_Busbridge

Hello,
I'm currently in full time employment but am considering starting my own part time business working 2 days a month.
What do I need to do in regards getting the own business registered and ensure I pay the correct HMRC deductions? Does me being in full time employment complicate things?
My plan is to earn an extra £150-300 a month. My current annual salary from my regular job is £22,500. I work for a large insurance company.  
I'm very confused by what I need to do to ensure I'm acting correctly. 
Thanks in advance.

Comms69

Depends on what the business is?
Depends if your employer allows this?
Depends if you plan to be in effect self employed (not that it's worth setting up a company for £3600). 

In terms of tax, put aside 40%. That way you've got ample when it comes to tax time.

Dox

Start here: https://www.gov.uk/browse/business

MinuteNoodles

Register as self employed. Once a year you fill in a self assessment where there's a section for income from your business and income from your employment. The profit/loss of your business is added to the income from your employment and the amount of tax you owe is calculated. The amount you've already paid via PAYE is deducted from that and you're sent a bill for the difference or a refund if you traded at a loss.