What you wanna do is use BRM (Bank roll management) when selecting an MTT to play.
So when you play an MTT-you dont want to be risking more than 2% of your roll.
So for example if you have $30 in your account you shouldnt be playing for more than 60 cent buyin for an MTT. So to play $1 MTTs you will need at least $50 in your account (MINIMUM).
If you have less than $50 my advice would be to play sngs where you can play 5% of your roll under BRM. If you have $30 in your account you can play $1 sngs until you build your roll up.
Main difference between MTTs and SNGs is the variance due to more players playing MTTs you will need to hit cards more often and have hands hold frequently to make the money then make the final table-where the real money is.
With proper BRM-your roll will be able to sustain a bad run while playing MTTs.
So to conclude: If you have at least $50 dolls i would advise you to play $1 mtts to learn how to play them and adjust to them. Id also advise you to keep playing Sngs (5% of roll remember!) to constantly boost your roll-especially if your playing MTTs as this should boost your roll at the same time. As your roll increases in size you should move up MTT buyins, however still be strict to 2% MTT and 5% SNG and you shouldnt go broke (I try to tell this to my friends but they wont listen and have to reload all the time. I havent had to deposit for like 7 months and its because i take BRM very seriously and so should you)
GL at the tables and if you have any questions feel free to message me or post below.
Discomonkeys advice is great so if you have any strategy questions etc i would post there also like gecko has said.