Hi Jake, I know you posted this a few days ago, but just adding my ten penneth:
Itsfishing has it about right, you haven't given us much information to go on so we can only draw conclusions, which may be way off the mark.
I'm using a lot of generalisations here as each situation will require tweaking, I will assume that you just want to increase the number of roach (and small bits) that you catch to begin with.
The rod and reel that you have is usable, but is probably not very well balanced; this doesn't mean that you have to rush out and buy a new rod or reel, what it means is that the reel is probably a bit big for the length and power of the rod (which is relatively soft) you are using.
You haven't identified the type of fish you are trying to catch (as itsfishing pointed out), but if you are happy trying to catch a few more roach, then you certainly need to look at getting a lighter line, say 4-5lb with as already said 2.5-3lb hook length, this should result in you getting a few more bites on its own as smaller fish seem to spook away from thickish line in the water. Believe it or not, you could still land carp and tench on this set up although it's not advisable to target them. So far as reel line is concerned, spider line (in my experience) is probably not a good choice as it is very stiff which will make casting a float difficult; although they do have quite a range out so I may be wrong. A good all round line which is cheap and can be bought in bulk for a tenner is Daiwa Sensor, you will need quite a bit to fill up your spool. (have you filled your spool to the lip?)
Hook size, will depend on the bait that you are using.
Bait, this will play a large part in how you shot your float as well as hook size. Maggots are a good choice for smaller fish as they work everywhere. They require a few small shot (8 - 12 depending on eye-site and dexterity) spread down the bottom half of the line so that the maggot doesn't fall too quickly matching your lose feed, a size 16 hook is probably as big as you want this time of year for roach and bits, 18 and 20 may also get you more bites when the going gets tuff.
Float, as said before, place most of you shot around the float leaving a bit of the float tip sticking out of the water so that it can be dotted down with the smaller shot (8 - 12, these are sometimes called dust shot). Another thing to do is use as few shot as you can around the float so that you can change depth easier. You only want the minimum amount of float sticking out of the water that you can see.
Sometimes, you may find that you have had you bait chewed; this indicates that you have had more bites than you have seen - slight movements of the float can indicate a bite, whereas, others times you have to wait until the float buries itself before you strike.
I presume that you are fishing a lake and fishing quite close in. If this is because you are having difficulty casting, then the above advice will help (get you further out if required) i.e. by changing line size and float shotting.
Well done for plumbing the depth, it's a good idea to get an underwater picture of the depth all around you, often there is a sharp drop in depth around a rod length (might be closer, might be further) out and the fish might patrol along the top middle or bottom of this area through the day or only stay in one place during your session. Start with your hook bait on the bottom.
Feeding, if using maggots, trickle 3 - 4 every few minutes (little and often) to begin with, if you get bites then it's a mixture of increasing quantity and or frequency and the opposite applies when bites are hard to come by. Just remember - you can't take them out.
When feeding little and often, especially in warm weather, the fish can 'come up in the water
' as they compete with each other to get to the bait first; this is where you want the bait to fall slowly through the water - having said that, you can sometimes get the bigger ones by letting the bait fall through the little'ns. It may be worth moving your float down the line so that the bait is higher in the water - then leave it in until your next feed when you would cast over the loose feed that you have just introduced. Try to gauge where in the water you are getting the bites and keep metal notes.
If things are slow, it might be worth 'laying on', this means moving the float up the line so that you are fishing over depth, it could be by less than an inch (2.5cm) or several feet (over a meter is not uncommon, but probably not needed for lake fishing in general for roach as a beginner).
I know that this a lot to take in, but should provide you with some help to catch a few and develop your confidence and ability. Tight lines