How to practise combo Earthbind and Poof continuously using Meepo?

Tab-Netting is a quick way of using multiple Meepos to hold a target in place.

Tab (Default) changes to the 'next' selected unit, so if you set up, for example, the keys 1 - 2 - 3 to be:

1: Select my hero
2: Select all other units
3: Select all units

And Press 3, then use net, tab > net > tab > net > tab > net and etc. you will cycle through every Meepo and use his skills one after the other.

For poofing, keeping sight of your main Meepo and using tab > poof onto it very quickly takes some practice, and quickcast on poof can be VERY helpful because it goes from 2 key-presses and a click to just 2 key-presses.

In general tips for Meepo: pick last, take mid or safelane, get an early point in every skill at level 4 with net > poof > ulti > geostrike and then maxing poof by level 7 is the best way to go about it, once you have your second Meepo you can use him to stack jungle while you lasthit at lane with your prime Meepo, then at level 7 a double-poof will kill just about any stacked camp, getting you great early levels and gold.

Item progression for me is generally getting 2 rings of protection and a salve to start, getting tranquil boots and a basillius (possibly built into Vlads) before going either blink or Aghs immediately depending on the game, (Aghs for a lead, blink for a comeback).

When you have 3 Meepos you can put one on a control group and have it constantly farm jungle, if you ever need backup you can simply poof him out, and he's also a reliable escape method if you need somewhere out of danger to poof to, this provides you with reliable extra XP and gold regardless of what you do with your main Meepo.

When you have Aghs and your blink the next items are pretty situational, Skadi is the best overall stat item in the game, and Meepo really likes stats.
Heart of tarrasque is great for tank, and a butterfly or possibly ethereal blade is amazing for the huge amount of agility giving you a really nice damage boost, as well as the bonus damage on blink > poof kills, you will rarely need extra intel items, but hex is very nice for the active. Boots of travel are also amazing, because 5 global teleports on a separate cooldown allows you to be anywhere anytime, becoming effectively the best rat hero, with the most mobility (boots), best wave clear(poof), and highest tower damage(5 goddamn Meepos) in the game.

(Eth blade is more of an advanced item, but saving a Meepo from right click focus can really destroy a teams ability to focus a weak Meepo, and can really mess with a single attacker)

Beware of: single target slows, AoE disables or nukes (especially echo slam), and the overall biggest counter to a Meepo : Winter wyvern, because the more powerful you get the harder you hit yourself.

Basically: get used to basic tab-netting and fast tab-poofing (I believe there are scripts for 1-key Tab-poofing but I've never used them myself), farm EVERYWHERE, get level 25 early and win the game by melting towers (and heroes) faster than any other hero in the game.

I am not a Meepo player but I know some tricks about him.

If I understand this correctly you are clicking each portrait with your mouse to control each Meepo? If that is the case I first of all suggest you to use the "Tab" key to cycle through your Meepos. Then you can click "W" on your first Meepo then click on the ground to poof. Then Tab to go to your next Meepo and click "W" then click on the ground. And repeat that for all your Meepos. This way you will at-least be able to poof a lot quicker with all your Meepos.

You should also use control groups to separate your Meepos in groups. Like a button for your main Meepo and one for all the others. You can make such a group by holding the Control key while having your specified group selected and hitting the target button you want to bind this group to. This way you don't accidentally poof Meepos to a place you don't want them.

You could practice this continuously in a private game with cheats enabled. You can type in the chat "-wtf" your spells won't have cooldown or use any Mana this way.