Hi Celtic Cub. If most of your clients/customers are VAT registered then it would generally make sense to register for VAT. This is because although you will have to charge VAT on your sales going forward, your customers can just claim it back so it makes no difference to their overall cost.
If your customers are generally not VAT registered, you have to decide whether you will keep your charges to them the same and then charge VAT on top - thus making the cost to them of using your services more expensive. Or you can choose to keep the overall price to them the same, but your own income will reduce as part of that amount then becomes payable to the Revenue as VAT.
The other general advantage of VAT registration is of course being able to claim back VAT on expenses. This may be of greater benefit to some depending on what type of costs you have etc. If for example your main costs are travel costs, you may find that there is not much VAT to reclaim anyway. However, the majority of people will have a good number of expenses for which VAT can be reclaimed.
Finally, you just need to be aware of the threshold at which you are obliged to register for VAT regardless of whether you would like to or not. And also, you need to be aware of the VAT rate applicable to your particular activity.