PYE Ratio?? Do you mean P/E Ratio, if so this is just one way but this can be manipulated. If you are serious about making money from equities then treat any investment as it should be done and in the manner it should be undertaken.
When you buy shares you are doing just that, buying a share in that particular company (or holding company as it may be). Therefore you need to treat it this way and ask the same questions you would if your mate came up to you and asked you for money for his business.
Some basics (and should be enjoyable) to do and watch for guidance in this is Dragons Den. You'll find this insightful as the questions they ask week in week out are very monotonous, its this for a reason. Also consider buying books on how to operate and run a business. I wont recommend any as there is a plethora out there to get your teeth in to.
Use Youtube or something similar to understand basics in understanding business's and also what you will find helpful is way to cook books, tax breaks, illegal operations, dividends etc.
Because you are looking to purchase a part of a company the price you pay will be governed by the person you are buying from and how much they want to sell for (in principal), therefore look to do research into supply and demand in this area as well.
IF THERE IS A FEW WORDS OF WARNING ITS THIS:
Look out for net profit against its credit line and understand the ideal/market average ratio for that entity.
Check out the management - these are the people who bring trust (or not) and a good/bad working relation to the company
Have some basic (at least) understanding about the industry you wish to invest in before moving forward with specifics
Check out the micro and macro limitations of the said entity and what other industries/companies directly affect the target company.
Look out for cash flow - cash is king and credit lines can dry up fast in any economic climate. Ratio's for this will be heavily dependent on each industry and will vary widely, have an understanding of this before getting excited when you find one or a group that seems (too) good.
Check statements dating back over last 5 years (no need to go further than this) and base you own judgement against the Directors forecasts of the same period. Also look and compare separately regarding brokers recommendations but beware that some brokers will be pushing the stock
If you are looking for capital growth then ensure the company is not giving all its profits to share holders. The same goes in reverse if you are looking for dividend payments - this will be covered under PE ratios.
These are some basics to look for and is in no way exhausted. I don't want to spoil all your fun on what could be a very exciting journey, enjoy the long and winding road and you shall make money but remember the old saying - Don't put all your eggs in one basket.
This is just a very basic guide to help you on your way.
If you buy in to one bank then also buy in to another or several others in the same sector.
The Reason: If one bank fails then that cash will go to another bank.
The same saying is also important to different sectors. ie, If you invest in banks then maybe throw some into other areas of the financial sector, investment services, insurers etc.
If you are buying a bag of blue chip shares then also consider throwing in some wild cards, a friend of mine recently bought Angel mining.... He made a tidy sum from this very quickly against both of our beliefs. Wild cards are best played in mining and pharmaceuticals as they can be very irrational and volatile. The drug market can be extremely volatile, especially if a drug gets passed 1st phase, even in pre-clinical phase and once word gets out these stocks can go silly, of course should it fail any future upcoming trials will quickly collapse and more so. Commodities can also be good but for wild cards you would want to throw money into smaller companies that are looking to acquire licenses or that are exercising these on the premise that the goods are buried under ground.
You can make ridiculous percentage returns in the many hundreds practically over night on these but also remember that you can lose the lot, however, you can only ever lose 100%. That's why the term is 'don't put all your eggs in one basket'.