I have some savings and would like to know how look after it.

how many months of savings of raw cash does one keep? In case of redundancy.....Six months worth?

I would like to buy a flat in about 3 years time. So any assets need to be readily liquid so I can pounch.

I have no credit card debt to pay except student loans.

This is how I am going to hold it; in these areas:

1. CASH ISA
2. CASH IN CURRENT ACCOUNT
3. CASH IN HOME SAFE (STERLING)
4. GOLD (PHYSICAL)

What percentage are people putting their money into?

I am not very apt at share dealings; if someone could convince me then I would include as
5. SHARES

Others - and I cant be bothered with the hassle
6. BTL

You could try some premium bonds?

Mr Joe.

A general guide to investing is to put a percentage of your investment equivalent to your age into bonds,and the rest into shares.
So if you're 43 (my age) and have 20k to invest,you put 8.6k into bonds and 11.4k into shares.
The theory is that the younger you are,the more you can afford to risk on shares,as you have longer to recover any short term losses.If your timescale for investment is just 3 years you should adopt a more cautious approach,as this is not a long time in investment terms.
If you don't know about shares and/or don't want to do the homework then choose a tracker fund or unit trust.

Mr Joe suggests premium bonds.They sound boring,but are actually quite good if you are a high rate tax payer,as your winnings are tax free.
Take the time to buy a book and read about it,but how you invest is really down to your attitude to risk.

In case of redundancy keep 3 to 6 months of your salary in safe,liquid savings accounts (including ISAs)