how do increase my total bonus and leveling up?

You need all parts of the beach hideaways in town to get the bonus so Yes they must be fully upgraded.
Start small
Here are the basics, but the link posted above really has a lot of your questions answered already
Clear your town completely
Send all characters on a four hour task
Make a note of your starting cash amount.
In 4 hours clear your town again.
Make a note of your end cash amount.
The difference in the two amounts is how much you can spend on KEMs every four hours
Buy the number of KEMs that you can afford with your earnings from 4 hours
Start the XP Collider right before your KEMs are ready Minimum 5 donuts for 24 hours
Finish building your KEMs
Rake in the xp and level up
Sell your KEMs immediately DO NOT STORE
Clear your town
Buy the same number of KEM as before
Repeat until the collider runs out
Keep track of how many donuts you make each time
As long as you make enough donuts to pay for the XP Collider, you're good.
Hopefully you will make many more
At first you will need to plug your donuts earned into Burns' Mystery Boxes. Just remember to keep some to activate the collider
This really is the best bang for your donuts to increase your bonus percent

Try to do this when you will definitely have the time to log in and collect every four hours

Are you activating the XP collider?
Sorry but this really is the "Fast" way that is free
You could buy some donuts and use them on the Burns' Mystery box and that would be faster. Just wouldn't be free.

I did think of one thing. If you played during last Halloween event, The Old Ruins digging game gives a lot of XP. Make sure to play it every day.

"04n7vk7ovhr1;c-2033641" wrote:
my xp collider is activated and got like 14 kem houses place. I just recently place down Krusty thing for 50k and I'm level 105. But after collecting xp from all 14 kem it is not enough xp level twice or four times. My total bonus is 139% right now going place remaining stuff from Springfield heights I finish that part whole quest line

If I am reading this right you are getting either 2 or more level ups from your KEM farm. At level 139 you will have a ton of quest lines from levels up to 60 to work on. I see you progressing well and as we all did. You're not going to find a magic way to jump levels extremely fast. It will take weeks to get up to say level 400. It takes a lot of grinding to get the first 500% multiplier, and then it starts getting easier. The posts from @EllieGuseman are wise, correct and well laid out. This is the tried and tested way forward. You will need a healthy dose of patience, but many of us who are now donut and cash rich look back fondly on the grinding days. There is an excitement in the anticipation and waiting for items that goes when you can just get everything. Enjoy the journey.

I’m not saying this is the fastest way anyone could level up (freemium), as I really like to sleep at night, but it was fairly quick. Springfield Heights buildings are now included in the multiplier - they were ‘hidden’ when I wrote the paragraph below. I prefer to do at least a 24 hour sample of income to determine how many KEM’s to build.

"Muhsterino;c-1583422" wrote:
I started my town on 12th January 2017 and reached 939 on 10th May 2017. Here is my personal log of using the collider:
https://i.imgur.com/8CGUQcKl.jpg
https://i.imgur.com/zstqb6Zl.jpg
I am now running the collider 24/7, results at the end of each set of 10 days:
Collider 2: Level 192 to 295 = 103 levels. Bonus 139.25%
Collider 3: Level 295 to 414 = 119 levels. Bonus 158.50% (mystery box purchases)
Collider 4: Level 414 to 538 = 124 levels. Bonus 170%
Collider 5: Level 538 to 668 = 130 levels. Bonus 189.75% (4 nukes from Eliminator, purchased 1 Knightboat with rebate offer and Faberge Egg)
Collider 6: Level 668 to 810 = 142 levels. Bonus 217%
Collider 7: Level 810 to 939 = 129 levels (1 day, 20 hours left on collider) Bonus 237.25%
My bonus is made up from:
CONFORMITY BONUS 4.5%
FREE ITEMS: Golden calf idol .75%, dirt pile .25%, 2 burning bushes (1%), 6 Mini nuclear warhead (2.25% each from Eliminator task, total 13.5%)
ITEMS FROM MYSTERY BOXES: tire fire 2%, 29 I&S signs (29%), 28 Channel 6 vans (56%)
ITEMS BOUGHT WITH DONUTS: Homers hammock .25%, 5 X Beach hideaways (100%), 2 X set of flags 15%, Faberge egg (3%), 6 Knightboats (12%)
ITEMS BOUGHT WITH DONUTS, no bonus: Tourists (60D)

Spoiler

http://i.imgur.com/LAeixUUl.jpg
http://i.imgur.com/Ug3ncROl.jpg
http://i.imgur.com/8jpqITvl.jpg
As I was trying to get to 939 as quickly as possible, I made no attempt to design and squashed everything into a small space, although I opened all the available land in Springfield Heights. I have 96 playable characters and 19 Lard Lads!

Other people's collider experiences can be found in this thread:
https://forums.ea.com/en/the-simpsons-tapped-out/discussion/94006/i-gave-up/p1

"04n7vk7ovhr1;c-2033980" wrote:
so the next building cost 40k but don't have a lot of cash to buy what I do?

Please don't misinterpret this as a criticism, its an observation. Perhaps you should just play the game. If you just started Dec 18th you are doing great, but there seems to be an unexplained urgency to having to get everything done, or you are looking to the forum for a 'walkthrough' Trust me, there are tons of right ways to proceed. You can stop trying to level, and just build cash and complete quests. Some people love that. You can not do any quests and concentrate solely on building multiplier, to use to create donuts. You could cycle characters on short term tasks to maximize revenue. You probably can't to them all, and the answer to your current question depends on what your goal is.

I suspect, but could be wrong, that based on your questions in this thread and others that your goal is to 'beat' the game as fast as possible. Unfortunately there is no "winning' point in this game. It is radically different to different people. Some are true designers, who spend hours creating beautiful art. Some are gatherers who dump everything they can accumulate in a pile, and go for more.

There are great hints threads, great threads on the different levels, and many of these have been given to you as links. I'm not trying to get you to stop asking questions, but take a second and enjoy the game and the great people here. That's what TSTO is about.

In regards to the next building, 40K seems like a lot now, but when you are generating millions a day it will not be. The 40K will get you a revenue generator, but if its not going to allow you to open up additional quests, it may not be the best use of that cash right now. Again, it depends on where you are try to go.

Many of us remember waiting days and days to build up the cash to get a building so we could complete a level.

Best of luck, but please have fun!

"EllieGuseman;c-2033639" wrote:
Are you activating the XP collider?
Sorry but this really is the "Fast" way that is free
You could buy some donuts and use them on the Burns' Mystery box and that would be faster. Just wouldn't be free.

This is best because buying donuts saves time and saves your nerves. ;)

Mystery boxes are the cheapest/best way to build your multiplier.
https://forums.ea.com/en/the-simpsons-tapped-out/discussion/234520/mystery-box-value-best-cost-efficiency#latest

I don't got donuts and where do you find those jet things people talk about

@04n7vk7ovhr1 here is a way to get donuts with your multiplier. Jet engine bikes are in the vault occasionally. https://forums.ea.com/en/the-simpsons-tapped-out/discussion/149536/kwik-e-mart-also-known-as-kem-farming-guide/p1