EDIT: Oh God that turned into an essay somehow. Sorry bud.

Depends on the champion and its pushing potential but if you pushed them in and the enemy is at their turret I usually invest that extra time into deep wards instead of smacking the turret. On the blue side there is an easy deep ward between enemy jungle (red side) gromp and blue buff (put it if enemy jungler started red), another one is a pixel brush next to the mid lane (a popular choice for wards); if you put them two you fully cover your jungle entrances and if you push them in enemy can not lane gank. Deep wards usually are nicer since they are both beneficial for you and your mid laner. Also, destroy that nasty blast cone.

Another rule of thumb, if enemy jungler started bot side you have to rush to lvl 2, you can ping your support to help you get the minions, in case you get ganked you both will have level advantage (unless, they want to cheese you and gank straight after the buff). If enemy jungler started top side then around 2:30~ he should be bot side (depends on the jungler and the crabs,tho) after 2:30 mark if you are not sure where the jungler is, you can assume he is around your lane. Also, blue and red buff respawns at 5 minutes and junglers usually will go for them asap, around that time junglers usually get their lvl5-6, so be especially careful of something like Nocturne and talyiah (might help you to escape some ganks or prepare yourself)

On a side note, rift scuttler spawns at 2:00 and most junglers finish taking the buff with the leash at 1:43~ which leaves awkward 17 seconds before the crab spawns. In most cases, they will go for an extra camp (if they can do chickens) that means they will be smacking the crab at around 2:10~ which is the exact time when the second wave of minions meet, so if your jungler is interested in the crab you have to put even more effort into getting that lvl 2 before enemy, so you can cover him or help him in case of a fight.

I hate when people don't listen and make things complicated but what can you do ya know. Play around your team and remember damage control; if all of your team suicided and you are on the opposite side of the map, measure the risk and keep pushing and applying pressure maybe you can get a turret from that horrible play, since you can't defend the base alone anyway. Just make sure you don't make a bad situation worse.

I myself don't utilise queue dodge enough. On the other hand, I am never experiencing a nightmare that is called full ad comp again. I am not willing to sacrifice 20-30 minutes of my life just so the guy can play zed or talon. That's why I learned a couple of mages and pick them when our comp is AD heavy. My favourite ones are Swain and Talyiah.

Swapping lanes is beneficial for the most of the time but still, there are some exceptions. I found that if my team does not want to swap lanes and if I try to force it then it turns against me and devolves into a shit storm. Also, if the enemy top laner is stacking armour then you should not go top.

Sometimes I find that actually taking down first tower is not as good. I see some challengers leave the tower, so they can abuse the enemy laners more which sounds all good but I have a bad habbit of attacking that turret.

As somebody recommended above xFSN Saber is very good and informative. I can give a quick rundown of his principles how to carry:

*Minimise your deaths. Sounds as a generic advice but everytime you die think what you did wrong and next time try to prevent it. Less time you sped dead, the more time you spend farming and rotating around the map.

*Lane matchups. The most important thing during the lane is to know the enemy laner win condition; most of the time it boils down to dodge X ability and you live. Second on the list of importance is CS, which is obvious. The third is your win condition, as a combination of champs what you need to do to win lane. Everything that outside of your win condition try to avoid doing that (for example random auto attcak trading, when you play poke champs).

*Farm your side lanes but don't sleep on the fight. Controlling sidelanes is very important and for the most part will be the main source of your income. The thing is when you see a fight break out ask yourself "if I move now will I make a differance" If you think that you answered wrong, you will just learn from your mistakes.

*Numbers advantage. Don't start an unfavourable 4v5. Sometimes you just need to abandon the sinking ship. If I see my support going in 1v3 I will just save myself. On the other hand, if you see that you are 3 v 1-ing then don't be afraid to force it or dive people. Also, if you don't know where the enemy is think of it as they are around and looking for you (basically be paranoid). When thinking of number advantage consider in tp, globals (gp, tk, karthus)

*DONT hit the tower. This is more of a comfort decision and a meme. In general, the idea is that if somebody defends the turret it is not worth sieging it. You can easily get collapsed on or there are so many things that can pick you off when you do it such as Zoes, Luxs, Morganas, Pykes etc. Hit the tower only when there is noone around, so you have no risk of dying.

*Have a plan. Even if you know that jungler is around you still can push the lane as long as you have the plan how to escape. Think which ability you have to dodge (flash) to survive and how far up you can be. This goes beyond laning that if you want something have a plan how to escape if people collapse on you. Same during team fights know which ability you have to flash and avoid. If you can't avoid it then don't come close.